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< title > Pathnames< / title >
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< h2 > Foundation< / h2 >
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<!-- Weave of 'Pathnames' generated by 7 -->
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< ul class = "crumbs" > < li > < a href = "../webs.html" > Home< / a > < / li > < li > < a href = "index.html" > foundation< / a > < / li > < li > < a href = "index.html#3" > Chapter 3: The Operating System< / a > < / li > < li > < b > Pathnames< / b > < / li > < / ul > < p class = "purpose" > To manage references to locations in the host computer's file system.< / p >
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< ul class = "toc" > < li > < a href = "#SP1" > § 1. About pathnames< / a > < / li > < li > < a href = "#SP2" > § 2. Home folder< / a > < / li > < li > < a href = "#SP3" > § 3. Installation folder< / a > < / li > < li > < a href = "#SP4" > § 4. Creation< / a > < / li > < li > < a href = "#SP5" > § 5. Text to pathnames< / a > < / li > < li > < a href = "#SP6" > § 6. Writer< / a > < / li > < li > < a href = "#SP7" > § 7. Relative pathnames< / a > < / li > < li > < a href = "#SP8" > § 8. Relative URLs< / a > < / li > < li > < a href = "#SP9" > § 9. Existence in the file system< / a > < / li > < li > < a href = "#SP10" > § 10. Directory synchronisation< / a > < / li > < / ul > < hr class = "tocbar" >
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< p class = "inwebparagraph" > < a id = "SP1" > < / a > < b > § 1. About pathnames. < / b > We use the word "pathname" to mean a file-system location of a folder (or
directory), and "filename" to mean a location of a file. For example:
< / p >
< pre class = "display" >
< span class = "plain" > /Users/rblackmore/Documents/Fireball< / span >
< / pre >
< p class = "inwebparagraph" > is a pathname, whereas
< / p >
< pre class = "display" >
< span class = "plain" > /Users/rblackmore/Documents/Fireball/whoosh.aiff< / span >
< / pre >
< p class = "inwebparagraph" > is a filename. All references to folder locations in the filing system will be
held internally as < code class = "display" > < span class = "extract" > pathname< / span > < / code > objects, and all references to file locations as
< code class = "display" > < span class = "extract" > filename< / span > < / code > objects. Once created, these are never destroyed or modified,
so that it's safe to store a pointer to a pathname or filename anywhere.
< / p >
< p class = "inwebparagraph" > Note that a pathname may well be hypothetical, that is, it may well
describe a folder which doesn't exist on disc.
< / p >
< p class = "inwebparagraph" > A full path is a linked list, but reverse-ordered: thus,
< / p >
< pre class = "display" >
< span class = "plain" > /Users/rblackmore/Documents/< / span >
< / pre >
< p class = "inwebparagraph" > would be represented as a pointer to the < code class = "display" > < span class = "extract" > pathname< / span > < / code > for "Documents", which
in turn points to one for "rblackmore", which in turn points to "/Users".
Thus the root of the filing system is represented by the null pointer.
< / p >
< p class = "inwebparagraph" > Each < code class = "display" > < span class = "extract" > pathname< / span > < / code > can represent only a single level in the hierarchy, and
its textual name is not allowed to contain the < code class = "display" > < span class = "extract" > FOLDER_SEPARATOR< / span > < / code > character,
with just one exception: the < code class = "display" > < span class = "extract" > pathname< / span > < / code > at the end of the chain is allowed
to begin with < code class = "display" > < span class = "extract" > FOLDER_SEPARATOR< / span > < / code > to denote that it's at the root of the
host file system.
< / p >
< pre class = "display" >
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< span class = "reserved" > typedef< / span > < span class = "plain" > < / span > < span class = "reserved" > struct< / span > < span class = "plain" > < / span > < span class = "reserved" > pathname< / span > < span class = "plain" > {< / span >
< span class = "reserved" > struct< / span > < span class = "plain" > < / span > < span class = "reserved" > text_stream< / span > < span class = "plain" > *< / span > < span class = "identifier" > intermediate< / span > < span class = "plain" > ;< / span >
< span class = "reserved" > struct< / span > < span class = "plain" > < / span > < span class = "reserved" > pathname< / span > < span class = "plain" > *< / span > < span class = "identifier" > pathname_of_parent< / span > < span class = "plain" > ;< / span >
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< span class = "reserved" > int< / span > < span class = "plain" > < / span > < span class = "identifier" > known_to_exist< / span > < span class = "plain" > ; < / span > < span class = "comment" > corresponds to a directory in the filing system< / span >
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< span class = "constant" > MEMORY_MANAGEMENT< / span >
< span class = "plain" > } < / span > < span class = "reserved" > pathname< / span > < span class = "plain" > ;< / span >
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< / pre >
< p class = "inwebparagraph" > < / p >
< p class = "endnote" > The structure pathname is accessed in 3/fln and here.< / p >
< p class = "inwebparagraph" > < a id = "SP2" > < / a > < b > § 2. Home folder. < / b > We get the path to the user's home folder from the environment variable
< code class = "display" > < span class = "extract" > HOME< / span > < / code > , if it exists.
< / p >
< pre class = "display" >
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< span class = "reserved" > pathname< / span > < span class = "plain" > *< / span > < span class = "identifier" > home_path< / span > < span class = "plain" > = < / span > < span class = "identifier" > NULL< / span > < span class = "plain" > ;< / span >
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< span class = "reserved" > void< / span > < span class = "plain" > < / span > < span class = "functiontext" > Pathnames::start< button class = "popup" onclick = "togglePopup('usagePopup189')" > ...< span class = "popuptext" id = "usagePopup189" > Usage of < b > Pathnames::start< / b > :< br > Foundation Module - < a href = "1-fm.html#SP8" > § 8< / a > < / span > < / button > < / span > < span class = "plain" > (< / span > < span class = "reserved" > void< / span > < span class = "plain" > ) {< / span >
< span class = "reserved" > char< / span > < span class = "plain" > *< / span > < span class = "identifier" > home< / span > < span class = "plain" > = (< / span > < span class = "reserved" > char< / span > < span class = "plain" > *) (< / span > < span class = "functiontext" > < a href = "1-wp.html#SP4" > Platform::getenv< / a > < / span > < span class = "plain" > (< / span > < span class = "string" > "HOME"< / span > < span class = "plain" > ));< / span >
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< span class = "reserved" > if< / span > < span class = "plain" > (< / span > < span class = "identifier" > home< / span > < span class = "plain" > ) {< / span >
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< span class = "reserved" > text_stream< / span > < span class = "plain" > *< / span > < span class = "identifier" > H< / span > < span class = "plain" > = < / span > < span class = "functiontext" > < a href = "4-sm.html#SP4" > Str::new_from_locale_string< / a > < / span > < span class = "plain" > (< / span > < span class = "identifier" > home< / span > < span class = "plain" > );< / span >
< span class = "identifier" > home_path< / span > < span class = "plain" > = < / span > < span class = "functiontext" > < a href = "#SP5" > Pathnames::from_text< / a > < / span > < span class = "plain" > (< / span > < span class = "identifier" > H< / span > < span class = "plain" > );< / span >
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< span class = "identifier" > home_path< / span > < span class = "plain" > -> < / span > < span class = "identifier" > known_to_exist< / span > < span class = "plain" > = < / span > < span class = "constant" > TRUE< / span > < span class = "plain" > ;< / span >
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< span class = "plain" > }< / span >
< span class = "plain" > }< / span >
< / pre >
< p class = "inwebparagraph" > < / p >
< p class = "inwebparagraph" > < a id = "SP3" > < / a > < b > § 3. Installation folder. < / b > < / p >
< pre class = "display" >
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< span class = "reserved" > pathname< / span > < span class = "plain" > *< / span > < span class = "identifier" > installation_path< / span > < span class = "plain" > = < / span > < span class = "identifier" > NULL< / span > < span class = "plain" > ;< / span >
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< span class = "reserved" > void< / span > < span class = "plain" > < / span > < span class = "functiontext" > Pathnames::set_installation_path< button class = "popup" onclick = "togglePopup('usagePopup190')" > ...< span class = "popuptext" id = "usagePopup190" > Usage of < b > Pathnames::set_installation_path< / b > :< br > Command Line Arguments - < a href = "3-cla.html#SP13_1" > § 13.1< / a > < / span > < / button > < / span > < span class = "plain" > (< / span > < span class = "reserved" > pathname< / span > < span class = "plain" > *< / span > < span class = "identifier" > P< / span > < span class = "plain" > ) {< / span >
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< span class = "identifier" > installation_path< / span > < span class = "plain" > = < / span > < span class = "identifier" > P< / span > < span class = "plain" > ;< / span >
< span class = "plain" > }< / span >
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< span class = "reserved" > pathname< / span > < span class = "plain" > *< / span > < span class = "functiontext" > Pathnames::installation_path< button class = "popup" onclick = "togglePopup('usagePopup191')" > ...< span class = "popuptext" id = "usagePopup191" > Usage of < b > Pathnames::installation_path< / b > :< br > none< / span > < / button > < / span > < span class = "plain" > (< / span > < span class = "reserved" > const< / span > < span class = "plain" > < / span > < span class = "reserved" > char< / span > < span class = "plain" > *< / span > < span class = "identifier" > V< / span > < span class = "plain" > , < / span > < span class = "reserved" > text_stream< / span > < span class = "plain" > *< / span > < span class = "identifier" > def< / span > < span class = "plain" > ) {< / span >
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< span class = "reserved" > if< / span > < span class = "plain" > (< / span > < span class = "identifier" > installation_path< / span > < span class = "plain" > ) < / span > < span class = "reserved" > return< / span > < span class = "plain" > < / span > < span class = "identifier" > installation_path< / span > < span class = "plain" > ;< / span >
< span class = "identifier" > wchar_t< / span > < span class = "plain" > < / span > < span class = "identifier" > where< / span > < span class = "plain" > [4*< / span > < span class = "constant" > MAX_FILENAME_LENGTH< / span > < span class = "plain" > ];< / span >
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< span class = "identifier" > where< / span > < span class = "plain" > [0] = < / span > < span class = "constant" > 0< / span > < span class = "plain" > ;< / span >
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< span class = "functiontext" > < a href = "1-wp.html#SP5" > Platform::where_am_i< / a > < / span > < span class = "plain" > (< / span > < span class = "identifier" > where< / span > < span class = "plain" > , < / span > < span class = "constant" > 4< / span > < span class = "plain" > *< / span > < span class = "constant" > MAX_FILENAME_LENGTH< / span > < span class = "plain" > );< / span >
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< span class = "reserved" > if< / span > < span class = "plain" > (< / span > < span class = "identifier" > where< / span > < span class = "plain" > [0]) {< / span >
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< span class = "reserved" > text_stream< / span > < span class = "plain" > *< / span > < span class = "identifier" > v< / span > < span class = "plain" > = < / span > < span class = "functiontext" > < a href = "4-sm.html#SP4" > Str::new_from_wide_string< / a > < / span > < span class = "plain" > (< / span > < span class = "identifier" > where< / span > < span class = "plain" > );< / span >
< span class = "reserved" > filename< / span > < span class = "plain" > *< / span > < span class = "identifier" > F< / span > < span class = "plain" > = < / span > < span class = "functiontext" > < a href = "3-fln.html#SP3" > Filenames::from_text< / a > < / span > < span class = "plain" > (< / span > < span class = "identifier" > v< / span > < span class = "plain" > );< / span >
< span class = "reserved" > pathname< / span > < span class = "plain" > *< / span > < span class = "identifier" > P< / span > < span class = "plain" > = < / span > < span class = "functiontext" > < a href = "3-fln.html#SP6" > Filenames::get_path_to< / a > < / span > < span class = "plain" > (< / span > < span class = "identifier" > F< / span > < span class = "plain" > );< / span >
< span class = "reserved" > if< / span > < span class = "plain" > ((< / span > < span class = "identifier" > P< / span > < span class = "plain" > ) & & (< / span > < span class = "functiontext" > < a href = "4-sm.html#SP18" > Str::eq< / a > < / span > < span class = "plain" > (< / span > < span class = "identifier" > P< / span > < span class = "plain" > -> < / span > < span class = "element" > intermediate< / span > < span class = "plain" > , < / span > < span class = "identifier" > I< / span > < span class = "string" > "Tangled"< / span > < span class = "plain" > )))< / span >
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< span class = "identifier" > P< / span > < span class = "plain" > = < / span > < span class = "identifier" > P< / span > < span class = "plain" > -> < / span > < span class = "element" > pathname_of_parent< / span > < span class = "plain" > ;< / span >
< span class = "reserved" > return< / span > < span class = "plain" > < / span > < span class = "identifier" > P< / span > < span class = "plain" > ;< / span >
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< span class = "plain" > }< / span >
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< span class = "reserved" > if< / span > < span class = "plain" > (< / span > < span class = "identifier" > V< / span > < span class = "plain" > ) {< / span >
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< span class = "reserved" > char< / span > < span class = "plain" > *< / span > < span class = "identifier" > val< / span > < span class = "plain" > = < / span > < span class = "functiontext" > < a href = "1-wp.html#SP4" > Platform::getenv< / a > < / span > < span class = "plain" > (< / span > < span class = "identifier" > V< / span > < span class = "plain" > );< / span >
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< span class = "reserved" > if< / span > < span class = "plain" > ((< / span > < span class = "identifier" > val< / span > < span class = "plain" > ) & & (< / span > < span class = "identifier" > val< / span > < span class = "plain" > [0])) {< / span >
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< span class = "reserved" > text_stream< / span > < span class = "plain" > *< / span > < span class = "identifier" > v< / span > < span class = "plain" > = < / span > < span class = "functiontext" > < a href = "4-sm.html#SP4" > Str::new_from_locale_string< / a > < / span > < span class = "plain" > (< / span > < span class = "identifier" > val< / span > < span class = "plain" > );< / span >
< span class = "reserved" > return< / span > < span class = "plain" > < / span > < span class = "functiontext" > < a href = "#SP5" > Pathnames::from_text< / a > < / span > < span class = "plain" > (< / span > < span class = "identifier" > v< / span > < span class = "plain" > );< / span >
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< span class = "plain" > }< / span >
< span class = "plain" > }< / span >
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< span class = "reserved" > if< / span > < span class = "plain" > (< / span > < span class = "identifier" > def< / span > < span class = "plain" > ) < / span > < span class = "reserved" > return< / span > < span class = "plain" > < / span > < span class = "functiontext" > < a href = "#SP5" > Pathnames::from_text< / a > < / span > < span class = "plain" > (< / span > < span class = "identifier" > def< / span > < span class = "plain" > );< / span >
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< span class = "reserved" > return< / span > < span class = "plain" > < / span > < span class = "identifier" > NULL< / span > < span class = "plain" > ;< / span >
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< span class = "plain" > }< / span >
< / pre >
< p class = "inwebparagraph" > < / p >
< p class = "inwebparagraph" > < a id = "SP4" > < / a > < b > § 4. Creation. < / b > A subfolder is made by taking an existing pathname (or possible < code class = "display" > < span class = "extract" > NULL< / span > < / code > ) and
then going one level deeper, using the supplied name.
< / p >
< pre class = "display" >
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< span class = "reserved" > pathname< / span > < span class = "plain" > *< / span > < span class = "functiontext" > Pathnames::subfolder< button class = "popup" onclick = "togglePopup('usagePopup192')" > ...< span class = "popuptext" id = "usagePopup192" > Usage of < b > Pathnames::subfolder< / b > :< br > Epub Ebooks - < a href = "5-ee.html#SP6" > § 6< / a > , < a href = "5-ee.html#SP6_2" > § 6.2< / a > < br > Web Structure - < a href = "8-ws.html#SP7_3_3_2" > § 7.3.3.2< / a > , < a href = "8-ws.html#SP7_2_2_4" > § 7.2.2.4< / a > < / span > < / button > < / span > < span class = "plain" > (< / span > < span class = "reserved" > pathname< / span > < span class = "plain" > *< / span > < span class = "identifier" > P< / span > < span class = "plain" > , < / span > < span class = "reserved" > text_stream< / span > < span class = "plain" > *< / span > < span class = "identifier" > folder_name< / span > < span class = "plain" > ) {< / span >
< span class = "reserved" > return< / span > < span class = "plain" > < / span > < span class = "functiontext" > < a href = "#SP4" > Pathnames::primitive< / a > < / span > < span class = "plain" > (< / span > < span class = "identifier" > folder_name< / span > < span class = "plain" > , < / span > < span class = "constant" > 0< / span > < span class = "plain" > , < / span > < span class = "functiontext" > < a href = "4-sm.html#SP8" > Str::len< / a > < / span > < span class = "plain" > (< / span > < span class = "identifier" > folder_name< / span > < span class = "plain" > ), < / span > < span class = "identifier" > P< / span > < span class = "plain" > );< / span >
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< span class = "plain" > }< / span >
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< span class = "reserved" > pathname< / span > < span class = "plain" > *< / span > < span class = "functiontext" > Pathnames::primitive< button class = "popup" onclick = "togglePopup('usagePopup193')" > ...< span class = "popuptext" id = "usagePopup193" > Usage of < b > Pathnames::primitive< / b > :< br > < a href = "#SP5" > § 5< / a > < / span > < / button > < / span > < span class = "plain" > (< / span > < span class = "reserved" > text_stream< / span > < span class = "plain" > *< / span > < span class = "identifier" > str< / span > < span class = "plain" > , < / span > < span class = "reserved" > int< / span > < span class = "plain" > < / span > < span class = "identifier" > from< / span > < span class = "plain" > , < / span > < span class = "reserved" > int< / span > < span class = "plain" > < / span > < span class = "identifier" > to< / span > < span class = "plain" > , < / span > < span class = "reserved" > pathname< / span > < span class = "plain" > *< / span > < span class = "identifier" > par< / span > < span class = "plain" > ) {< / span >
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< span class = "reserved" > pathname< / span > < span class = "plain" > *< / span > < span class = "identifier" > P< / span > < span class = "plain" > = < / span > < span class = "identifier" > CREATE< / span > < span class = "plain" > (< / span > < span class = "reserved" > pathname< / span > < span class = "plain" > );< / span >
< span class = "identifier" > P< / span > < span class = "plain" > -> < / span > < span class = "element" > pathname_of_parent< / span > < span class = "plain" > = < / span > < span class = "identifier" > par< / span > < span class = "plain" > ;< / span >
< span class = "identifier" > P< / span > < span class = "plain" > -> < / span > < span class = "element" > known_to_exist< / span > < span class = "plain" > = < / span > < span class = "constant" > FALSE< / span > < span class = "plain" > ;< / span >
< span class = "reserved" > if< / span > < span class = "plain" > (< / span > < span class = "identifier" > to< / span > < span class = "plain" > -< / span > < span class = "identifier" > from< / span > < span class = "plain" > < = < / span > < span class = "constant" > 0< / span > < span class = "plain" > ) < / span > < span class = "identifier" > internal_error< / span > < span class = "plain" > (< / span > < span class = "string" > "empty intermediate pathname"< / span > < span class = "plain" > );< / span >
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< span class = "identifier" > P< / span > < span class = "plain" > -> < / span > < span class = "element" > intermediate< / span > < span class = "plain" > = < / span > < span class = "functiontext" > < a href = "4-sm.html#SP2" > Str::new_with_capacity< / a > < / span > < span class = "plain" > (< / span > < span class = "identifier" > to< / span > < span class = "plain" > -< / span > < span class = "identifier" > from< / span > < span class = "plain" > +1);< / span >
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< span class = "reserved" > if< / span > < span class = "plain" > (< / span > < span class = "identifier" > str< / span > < span class = "plain" > )< / span >
< span class = "reserved" > for< / span > < span class = "plain" > (< / span > < span class = "reserved" > int< / span > < span class = "plain" > < / span > < span class = "identifier" > i< / span > < span class = "plain" > = < / span > < span class = "identifier" > from< / span > < span class = "plain" > ; < / span > < span class = "identifier" > i< / span > < span class = "plain" > < < / span > < span class = "identifier" > to< / span > < span class = "plain" > ; < / span > < span class = "identifier" > i< / span > < span class = "plain" > ++)< / span >
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< span class = "identifier" > PUT_TO< / span > < span class = "plain" > (< / span > < span class = "identifier" > P< / span > < span class = "plain" > -> < / span > < span class = "identifier" > intermediate< / span > < span class = "plain" > , < / span > < span class = "functiontext" > < a href = "4-sm.html#SP13" > Str::get< / a > < / span > < span class = "plain" > (< / span > < span class = "functiontext" > < a href = "4-sm.html#SP10" > Str::at< / a > < / span > < span class = "plain" > (< / span > < span class = "identifier" > str< / span > < span class = "plain" > , < / span > < span class = "identifier" > i< / span > < span class = "plain" > )));< / span >
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< span class = "reserved" > return< / span > < span class = "plain" > < / span > < span class = "identifier" > P< / span > < span class = "plain" > ;< / span >
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< span class = "plain" > }< / span >
< / pre >
< p class = "inwebparagraph" > < / p >
< p class = "inwebparagraph" > < a id = "SP5" > < / a > < b > § 5. Text to pathnames. < / b > The following takes a text of a name and returns a pathname,
possibly relative to the home folder. Empty folder names are ignored
except possibly for an initial slash, so for example < code class = "display" > < span class = "extract" > paris/roubaix< / span > < / code > ,
< code class = "display" > < span class = "extract" > paris//roubaix< / span > < / code > and < code class = "display" > < span class = "extract" > paris/roubaix/< / span > < / code > are indistinguishable here, but
< code class = "display" > < span class = "extract" > /paris/roubaix< / span > < / code > is different.
< / p >
< pre class = "display" >
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< span class = "reserved" > pathname< / span > < span class = "plain" > *< / span > < span class = "functiontext" > Pathnames::from_text< button class = "popup" onclick = "togglePopup('usagePopup194')" > ...< span class = "popuptext" id = "usagePopup194" > Usage of < b > Pathnames::from_text< / b > :< br > < a href = "#SP2" > § 2< / a > , < a href = "#SP3" > § 3< / a > , Command Line Arguments - < a href = "3-cla.html#SP13_1" > § 13.1< / a > , < a href = "3-cla.html#SP13_1_1" > § 13.1.1< / a > < br > Filenames - < a href = "3-fln.html#SP3" > § 3< / a > < br > Epub Ebooks - < a href = "5-ee.html#SP7_4" > § 7.4< / a > < / span > < / button > < / span > < span class = "plain" > (< / span > < span class = "reserved" > text_stream< / span > < span class = "plain" > *< / span > < span class = "identifier" > path< / span > < span class = "plain" > ) {< / span >
< span class = "reserved" > return< / span > < span class = "plain" > < / span > < span class = "functiontext" > < a href = "#SP5" > Pathnames::from_text_relative< / a > < / span > < span class = "plain" > (< / span > < span class = "identifier" > NULL< / span > < span class = "plain" > , < / span > < span class = "identifier" > path< / span > < span class = "plain" > );< / span >
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< span class = "plain" > }< / span >
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< span class = "reserved" > pathname< / span > < span class = "plain" > *< / span > < span class = "functiontext" > Pathnames::from_text_relative< button class = "popup" onclick = "togglePopup('usagePopup195')" > ...< span class = "popuptext" id = "usagePopup195" > Usage of < b > Pathnames::from_text_relative< / b > :< br > Web Modules - < a href = "8-wm.html#SP7" > § 7< / a > < / span > < / button > < / span > < span class = "plain" > (< / span > < span class = "reserved" > pathname< / span > < span class = "plain" > *< / span > < span class = "identifier" > P< / span > < span class = "plain" > , < / span > < span class = "reserved" > text_stream< / span > < span class = "plain" > *< / span > < span class = "identifier" > path< / span > < span class = "plain" > ) {< / span >
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< span class = "reserved" > pathname< / span > < span class = "plain" > *< / span > < span class = "identifier" > at< / span > < span class = "plain" > = < / span > < span class = "identifier" > P< / span > < span class = "plain" > ;< / span >
< span class = "reserved" > int< / span > < span class = "plain" > < / span > < span class = "identifier" > i< / span > < span class = "plain" > = < / span > < span class = "constant" > 0< / span > < span class = "plain" > , < / span > < span class = "identifier" > pos< / span > < span class = "plain" > = < / span > < span class = "constant" > 0< / span > < span class = "plain" > ;< / span >
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< span class = "reserved" > if< / span > < span class = "plain" > ((< / span > < span class = "functiontext" > < a href = "4-sm.html#SP13" > Str::get< / a > < / span > < span class = "plain" > (< / span > < span class = "functiontext" > < a href = "4-sm.html#SP10" > Str::start< / a > < / span > < span class = "plain" > (< / span > < span class = "identifier" > path< / span > < span class = "plain" > ))) & & (< / span > < span class = "identifier" > P< / span > < span class = "plain" > == < / span > < span class = "identifier" > NULL< / span > < span class = "plain" > )) < / span > < span class = "identifier" > i< / span > < span class = "plain" > ++;< / span >
< span class = "reserved" > for< / span > < span class = "plain" > (; < / span > < span class = "identifier" > i< / span > < span class = "plain" > < < / span > < span class = "functiontext" > < a href = "4-sm.html#SP8" > Str::len< / a > < / span > < span class = "plain" > (< / span > < span class = "identifier" > path< / span > < span class = "plain" > ); < / span > < span class = "identifier" > i< / span > < span class = "plain" > ++)< / span >
< span class = "reserved" > if< / span > < span class = "plain" > (< / span > < span class = "functiontext" > < a href = "4-sm.html#SP13" > Str::get< / a > < / span > < span class = "plain" > (< / span > < span class = "functiontext" > < a href = "4-sm.html#SP10" > Str::at< / a > < / span > < span class = "plain" > (< / span > < span class = "identifier" > path< / span > < span class = "plain" > , < / span > < span class = "identifier" > i< / span > < span class = "plain" > )) == < / span > < span class = "constant" > FOLDER_SEPARATOR< / span > < span class = "plain" > ) {< / span >
< span class = "reserved" > if< / span > < span class = "plain" > (< / span > < span class = "identifier" > i< / span > < span class = "plain" > > < / span > < span class = "identifier" > pos< / span > < span class = "plain" > ) < / span > < span class = "identifier" > at< / span > < span class = "plain" > = < / span > < span class = "functiontext" > < a href = "#SP4" > Pathnames::primitive< / a > < / span > < span class = "plain" > (< / span > < span class = "identifier" > path< / span > < span class = "plain" > , < / span > < span class = "identifier" > pos< / span > < span class = "plain" > , < / span > < span class = "identifier" > i< / span > < span class = "plain" > , < / span > < span class = "identifier" > at< / span > < span class = "plain" > );< / span >
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< span class = "identifier" > pos< / span > < span class = "plain" > = < / span > < span class = "identifier" > i< / span > < span class = "plain" > +1;< / span >
< span class = "plain" > }< / span >
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< span class = "reserved" > if< / span > < span class = "plain" > (< / span > < span class = "identifier" > i< / span > < span class = "plain" > > < / span > < span class = "identifier" > pos< / span > < span class = "plain" > ) < / span > < span class = "identifier" > at< / span > < span class = "plain" > = < / span > < span class = "functiontext" > < a href = "#SP4" > Pathnames::primitive< / a > < / span > < span class = "plain" > (< / span > < span class = "identifier" > path< / span > < span class = "plain" > , < / span > < span class = "identifier" > pos< / span > < span class = "plain" > , < / span > < span class = "identifier" > i< / span > < span class = "plain" > , < / span > < span class = "identifier" > at< / span > < span class = "plain" > );< / span >
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< span class = "reserved" > return< / span > < span class = "plain" > < / span > < span class = "identifier" > at< / span > < span class = "plain" > ;< / span >
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< span class = "plain" > }< / span >
< / pre >
< p class = "inwebparagraph" > < / p >
< p class = "inwebparagraph" > < a id = "SP6" > < / a > < b > § 6. Writer. < / b > Conversely, by the miracle of depth-first recursion:
< / p >
< pre class = "display" >
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< span class = "reserved" > void< / span > < span class = "plain" > < / span > < span class = "functiontext" > Pathnames::writer< button class = "popup" onclick = "togglePopup('usagePopup196')" > ...< span class = "popuptext" id = "usagePopup196" > Usage of < b > Pathnames::writer< / b > :< br > Foundation Module - < a href = "1-fm.html#SP8_1" > § 8.1< / a > < br > Filenames - < a href = "3-fln.html#SP4" > § 4< / a > < / span > < / button > < / span > < span class = "plain" > (< / span > < span class = "constant" > OUTPUT_STREAM< / span > < span class = "plain" > , < / span > < span class = "reserved" > char< / span > < span class = "plain" > *< / span > < span class = "identifier" > format_string< / span > < span class = "plain" > , < / span > < span class = "reserved" > void< / span > < span class = "plain" > *< / span > < span class = "identifier" > vP< / span > < span class = "plain" > ) {< / span >
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< span class = "reserved" > pathname< / span > < span class = "plain" > *< / span > < span class = "identifier" > P< / span > < span class = "plain" > = (< / span > < span class = "reserved" > pathname< / span > < span class = "plain" > *) < / span > < span class = "identifier" > vP< / span > < span class = "plain" > ;< / span >
< span class = "reserved" > int< / span > < span class = "plain" > < / span > < span class = "identifier" > divider< / span > < span class = "plain" > = < / span > < span class = "constant" > FOLDER_SEPARATOR< / span > < span class = "plain" > ;< / span >
< span class = "reserved" > if< / span > < span class = "plain" > (< / span > < span class = "identifier" > format_string< / span > < span class = "plain" > [0] == < / span > < span class = "character" > '/'< / span > < span class = "plain" > ) < / span > < span class = "identifier" > divider< / span > < span class = "plain" > = < / span > < span class = "character" > '/'< / span > < span class = "plain" > ;< / span >
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< span class = "reserved" > if< / span > < span class = "plain" > (< / span > < span class = "identifier" > P< / span > < span class = "plain" > ) < / span > < span class = "functiontext" > < a href = "#SP6" > Pathnames::writer_r< / a > < / span > < span class = "plain" > (< / span > < span class = "identifier" > OUT< / span > < span class = "plain" > , < / span > < span class = "identifier" > P< / span > < span class = "plain" > , < / span > < span class = "identifier" > divider< / span > < span class = "plain" > ); < / span > < span class = "reserved" > else< / span > < span class = "plain" > < / span > < span class = "identifier" > WRITE< / span > < span class = "plain" > (< / span > < span class = "string" > "."< / span > < span class = "plain" > );< / span >
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< span class = "plain" > }< / span >
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< span class = "reserved" > void< / span > < span class = "plain" > < / span > < span class = "functiontext" > Pathnames::writer_r< button class = "popup" onclick = "togglePopup('usagePopup197')" > ...< span class = "popuptext" id = "usagePopup197" > Usage of < b > Pathnames::writer_r< / b > :< br > none< / span > < / button > < / span > < span class = "plain" > (< / span > < span class = "constant" > OUTPUT_STREAM< / span > < span class = "plain" > , < / span > < span class = "reserved" > pathname< / span > < span class = "plain" > *< / span > < span class = "identifier" > P< / span > < span class = "plain" > , < / span > < span class = "reserved" > int< / span > < span class = "plain" > < / span > < span class = "identifier" > divider< / span > < span class = "plain" > ) {< / span >
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< span class = "reserved" > if< / span > < span class = "plain" > (< / span > < span class = "identifier" > P< / span > < span class = "plain" > -> < / span > < span class = "element" > pathname_of_parent< / span > < span class = "plain" > ) {< / span >
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< span class = "functiontext" > < a href = "#SP6" > Pathnames::writer_r< / a > < / span > < span class = "plain" > (< / span > < span class = "identifier" > OUT< / span > < span class = "plain" > , < / span > < span class = "identifier" > P< / span > < span class = "plain" > -> < / span > < span class = "element" > pathname_of_parent< / span > < span class = "plain" > , < / span > < span class = "identifier" > divider< / span > < span class = "plain" > );< / span >
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< span class = "identifier" > PUT< / span > < span class = "plain" > (< / span > < span class = "identifier" > divider< / span > < span class = "plain" > );< / span >
< span class = "plain" > }< / span >
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< span class = "identifier" > WRITE< / span > < span class = "plain" > (< / span > < span class = "string" > "%S"< / span > < span class = "plain" > , < / span > < span class = "identifier" > P< / span > < span class = "plain" > -> < / span > < span class = "element" > intermediate< / span > < span class = "plain" > );< / span >
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< span class = "plain" > }< / span >
< / pre >
< p class = "inwebparagraph" > < / p >
< p class = "inwebparagraph" > < a id = "SP7" > < / a > < b > § 7. Relative pathnames. < / b > Occasionally we want to shorten a pathname relative to another one:
for example,
< / p >
< pre class = "display" >
< span class = "plain" > /Users/rblackmore/Documents/Fireball/tablature< / span >
< / pre >
< p class = "inwebparagraph" > relative to
< / p >
< pre class = "display" >
< span class = "plain" > /Users/rblackmore/Documents/< / span >
< / pre >
< p class = "inwebparagraph" > would be
< / p >
< pre class = "display" >
< span class = "plain" > Fireball/tablature< / span >
< / pre >
< p class = "inwebparagraph" > Note that this does not correctly handle symlinks, < code class = "display" > < span class = "extract" > .< / span > < / code > , < code class = "display" > < span class = "extract" > ..< / span > < / code > and so on,
so it's probably not wise to use it with filenames typed in at the command
line.
< / p >
< pre class = "display" >
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< span class = "reserved" > void< / span > < span class = "plain" > < / span > < span class = "functiontext" > Pathnames::to_text_relative< button class = "popup" onclick = "togglePopup('usagePopup198')" > ...< span class = "popuptext" id = "usagePopup198" > Usage of < b > Pathnames::to_text_relative< / b > :< br > none< / span > < / button > < / span > < span class = "plain" > (< / span > < span class = "constant" > OUTPUT_STREAM< / span > < span class = "plain" > , < / span > < span class = "reserved" > pathname< / span > < span class = "plain" > *< / span > < span class = "identifier" > P< / span > < span class = "plain" > , < / span > < span class = "reserved" > pathname< / span > < span class = "plain" > *< / span > < span class = "identifier" > R< / span > < span class = "plain" > ) {< / span >
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< span class = "identifier" > TEMPORARY_TEXT< / span > < span class = "plain" > (< / span > < span class = "identifier" > rt< / span > < span class = "plain" > );< / span >
< span class = "identifier" > TEMPORARY_TEXT< / span > < span class = "plain" > (< / span > < span class = "identifier" > pt< / span > < span class = "plain" > );< / span >
< span class = "identifier" > WRITE_TO< / span > < span class = "plain" > (< / span > < span class = "identifier" > rt< / span > < span class = "plain" > , < / span > < span class = "string" > "%p"< / span > < span class = "plain" > , < / span > < span class = "identifier" > R< / span > < span class = "plain" > );< / span >
< span class = "identifier" > WRITE_TO< / span > < span class = "plain" > (< / span > < span class = "identifier" > pt< / span > < span class = "plain" > , < / span > < span class = "string" > "%p"< / span > < span class = "plain" > , < / span > < span class = "identifier" > P< / span > < span class = "plain" > );< / span >
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< span class = "reserved" > int< / span > < span class = "plain" > < / span > < span class = "identifier" > n< / span > < span class = "plain" > = < / span > < span class = "functiontext" > < a href = "4-sm.html#SP8" > Str::len< / a > < / span > < span class = "plain" > (< / span > < span class = "identifier" > pt< / span > < span class = "plain" > );< / span >
< span class = "reserved" > if< / span > < span class = "plain" > ((< / span > < span class = "functiontext" > < a href = "4-sm.html#SP20" > Str::prefix_eq< / a > < / span > < span class = "plain" > (< / span > < span class = "identifier" > rt< / span > < span class = "plain" > , < / span > < span class = "identifier" > pt< / span > < span class = "plain" > , < / span > < span class = "identifier" > n< / span > < span class = "plain" > )) & & (< / span > < span class = "functiontext" > < a href = "4-sm.html#SP13" > Str::get_at< / a > < / span > < span class = "plain" > (< / span > < span class = "identifier" > rt< / span > < span class = "plain" > , < / span > < span class = "identifier" > n< / span > < span class = "plain" > )==< / span > < span class = "constant" > FOLDER_SEPARATOR< / span > < span class = "plain" > )) {< / span >
< span class = "functiontext" > < a href = "4-sm.html#SP24" > Str::delete_n_characters< / a > < / span > < span class = "plain" > (< / span > < span class = "identifier" > rt< / span > < span class = "plain" > , < / span > < span class = "identifier" > n< / span > < span class = "plain" > +1);< / span >
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< span class = "identifier" > WRITE< / span > < span class = "plain" > (< / span > < span class = "string" > "%S"< / span > < span class = "plain" > , < / span > < span class = "identifier" > rt< / span > < span class = "plain" > );< / span >
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< span class = "plain" > } < / span > < span class = "reserved" > else< / span > < span class = "plain" > < / span > < span class = "identifier" > internal_error< / span > < span class = "plain" > (< / span > < span class = "string" > "pathname not relative to pathname"< / span > < span class = "plain" > );< / span >
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< span class = "identifier" > DISCARD_TEXT< / span > < span class = "plain" > (< / span > < span class = "identifier" > rt< / span > < span class = "plain" > );< / span >
< span class = "identifier" > DISCARD_TEXT< / span > < span class = "plain" > (< / span > < span class = "identifier" > pt< / span > < span class = "plain" > );< / span >
< span class = "plain" > }< / span >
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< span class = "reserved" > pathname< / span > < span class = "plain" > *< / span > < span class = "functiontext" > Pathnames::up< button class = "popup" onclick = "togglePopup('usagePopup199')" > ...< span class = "popuptext" id = "usagePopup199" > Usage of < b > Pathnames::up< / b > :< br > < a href = "#SP8" > § 8< / a > , Web Modules - < a href = "8-wm.html#SP7" > § 7< / a > < / span > < / button > < / span > < span class = "plain" > (< / span > < span class = "reserved" > pathname< / span > < span class = "plain" > *< / span > < span class = "identifier" > P< / span > < span class = "plain" > ) {< / span >
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< span class = "reserved" > if< / span > < span class = "plain" > (< / span > < span class = "identifier" > P< / span > < span class = "plain" > == < / span > < span class = "identifier" > NULL< / span > < span class = "plain" > ) < / span > < span class = "identifier" > internal_error< / span > < span class = "plain" > (< / span > < span class = "string" > "can't go up from root directory"< / span > < span class = "plain" > );< / span >
< span class = "reserved" > return< / span > < span class = "plain" > < / span > < span class = "identifier" > P< / span > < span class = "plain" > -> < / span > < span class = "identifier" > pathname_of_parent< / span > < span class = "plain" > ;< / span >
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< span class = "plain" > }< / span >
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< span class = "reserved" > text_stream< / span > < span class = "plain" > *< / span > < span class = "functiontext" > Pathnames::directory_name< button class = "popup" onclick = "togglePopup('usagePopup200')" > ...< span class = "popuptext" id = "usagePopup200" > Usage of < b > Pathnames::directory_name< / b > :< br > none< / span > < / button > < / span > < span class = "plain" > (< / span > < span class = "reserved" > pathname< / span > < span class = "plain" > *< / span > < span class = "identifier" > P< / span > < span class = "plain" > ) {< / span >
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< span class = "reserved" > if< / span > < span class = "plain" > (< / span > < span class = "identifier" > P< / span > < span class = "plain" > == < / span > < span class = "identifier" > NULL< / span > < span class = "plain" > ) < / span > < span class = "reserved" > return< / span > < span class = "plain" > < / span > < span class = "identifier" > NULL< / span > < span class = "plain" > ;< / span >
< span class = "reserved" > return< / span > < span class = "plain" > < / span > < span class = "identifier" > P< / span > < span class = "plain" > -> < / span > < span class = "identifier" > intermediate< / span > < span class = "plain" > ;< / span >
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< span class = "plain" > }< / span >
< / pre >
< p class = "inwebparagraph" > < / p >
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< p class = "inwebparagraph" > < a id = "SP8" > < / a > < b > § 8. Relative URLs. < / b > Suppose a web page in the directory at < code class = "display" > < span class = "extract" > from< / span > < / code > wants to link to a page in
the directory < code class = "display" > < span class = "extract" > to< / span > < / code > . The following composes a minimal-length URL to do so:
possibly, if they are in fact the same directory, an empty one.
< / p >
< pre class = "display" >
< span class = "reserved" > void< / span > < span class = "plain" > < / span > < span class = "functiontext" > Pathnames::relative_URL< button class = "popup" onclick = "togglePopup('usagePopup201')" > ...< span class = "popuptext" id = "usagePopup201" > Usage of < b > Pathnames::relative_URL< / b > :< br > none< / span > < / button > < / span > < span class = "plain" > (< / span > < span class = "constant" > OUTPUT_STREAM< / span > < span class = "plain" > , < / span > < span class = "reserved" > pathname< / span > < span class = "plain" > *< / span > < span class = "identifier" > from< / span > < span class = "plain" > , < / span > < span class = "reserved" > pathname< / span > < span class = "plain" > *< / span > < span class = "identifier" > to< / span > < span class = "plain" > ) {< / span >
< span class = "reserved" > int< / span > < span class = "plain" > < / span > < span class = "identifier" > found< / span > < span class = "plain" > = < / span > < span class = "constant" > FALSE< / span > < span class = "plain" > ;< / span >
< span class = "reserved" > for< / span > < span class = "plain" > (< / span > < span class = "reserved" > pathname< / span > < span class = "plain" > *< / span > < span class = "identifier" > P< / span > < span class = "plain" > = < / span > < span class = "identifier" > to< / span > < span class = "plain" > ; < / span > < span class = "identifier" > P< / span > < span class = "plain" > & & (< / span > < span class = "identifier" > found< / span > < span class = "plain" > == < / span > < span class = "constant" > FALSE< / span > < span class = "plain" > ); < / span > < span class = "identifier" > P< / span > < span class = "plain" > = < / span > < span class = "functiontext" > < a href = "#SP7" > Pathnames::up< / a > < / span > < span class = "plain" > (< / span > < span class = "identifier" > P< / span > < span class = "plain" > )) {< / span >
< span class = "identifier" > TEMPORARY_TEXT< / span > < span class = "plain" > (< / span > < span class = "identifier" > PT< / span > < span class = "plain" > );< / span >
< span class = "identifier" > WRITE_TO< / span > < span class = "plain" > (< / span > < span class = "identifier" > PT< / span > < span class = "plain" > , < / span > < span class = "string" > "%p"< / span > < span class = "plain" > , < / span > < span class = "identifier" > P< / span > < span class = "plain" > );< / span >
< span class = "reserved" > int< / span > < span class = "plain" > < / span > < span class = "identifier" > q_up_count< / span > < span class = "plain" > = < / span > < span class = "constant" > 0< / span > < span class = "plain" > ;< / span >
< span class = "reserved" > for< / span > < span class = "plain" > (< / span > < span class = "reserved" > pathname< / span > < span class = "plain" > *< / span > < span class = "identifier" > Q< / span > < span class = "plain" > = < / span > < span class = "identifier" > from< / span > < span class = "plain" > ; < / span > < span class = "identifier" > Q< / span > < span class = "plain" > & & (< / span > < span class = "identifier" > found< / span > < span class = "plain" > == < / span > < span class = "constant" > FALSE< / span > < span class = "plain" > ); < / span > < span class = "identifier" > Q< / span > < span class = "plain" > = < / span > < span class = "functiontext" > < a href = "#SP7" > Pathnames::up< / a > < / span > < span class = "plain" > (< / span > < span class = "identifier" > Q< / span > < span class = "plain" > )) {< / span >
< span class = "identifier" > TEMPORARY_TEXT< / span > < span class = "plain" > (< / span > < span class = "identifier" > QT< / span > < span class = "plain" > );< / span >
< span class = "identifier" > WRITE_TO< / span > < span class = "plain" > (< / span > < span class = "identifier" > QT< / span > < span class = "plain" > , < / span > < span class = "string" > "%p"< / span > < span class = "plain" > , < / span > < span class = "identifier" > Q< / span > < span class = "plain" > );< / span >
< span class = "reserved" > if< / span > < span class = "plain" > (< / span > < span class = "functiontext" > < a href = "4-sm.html#SP18" > Str::eq< / a > < / span > < span class = "plain" > (< / span > < span class = "identifier" > PT< / span > < span class = "plain" > , < / span > < span class = "identifier" > QT< / span > < span class = "plain" > )) {< / span >
< span class = "reserved" > for< / span > < span class = "plain" > (< / span > < span class = "reserved" > int< / span > < span class = "plain" > < / span > < span class = "identifier" > i< / span > < span class = "plain" > =0; < / span > < span class = "identifier" > i< / span > < span class = "plain" > < < / span > < span class = "identifier" > q_up_count< / span > < span class = "plain" > ; < / span > < span class = "identifier" > i< / span > < span class = "plain" > ++)< / span >
< span class = "identifier" > WRITE< / span > < span class = "plain" > (< / span > < span class = "string" > "../"< / span > < span class = "plain" > );< / span >
< span class = "identifier" > TEMPORARY_TEXT< / span > < span class = "plain" > (< / span > < span class = "identifier" > FPT< / span > < span class = "plain" > );< / span >
< span class = "identifier" > WRITE_TO< / span > < span class = "plain" > (< / span > < span class = "identifier" > FPT< / span > < span class = "plain" > , < / span > < span class = "string" > "%p"< / span > < span class = "plain" > , < / span > < span class = "identifier" > to< / span > < span class = "plain" > );< / span >
< span class = "functiontext" > < a href = "4-sm.html#SP25" > Str::substr< / a > < / span > < span class = "plain" > (< / span > < span class = "identifier" > OUT< / span > < span class = "plain" > , < / span > < span class = "functiontext" > < a href = "4-sm.html#SP10" > Str::at< / a > < / span > < span class = "plain" > (< / span > < span class = "identifier" > FPT< / span > < span class = "plain" > , < / span > < span class = "functiontext" > < a href = "4-sm.html#SP8" > Str::len< / a > < / span > < span class = "plain" > (< / span > < span class = "identifier" > PT< / span > < span class = "plain" > ) + < / span > < span class = "constant" > 1< / span > < span class = "plain" > ), < / span > < span class = "functiontext" > < a href = "4-sm.html#SP10" > Str::end< / a > < / span > < span class = "plain" > (< / span > < span class = "identifier" > FPT< / span > < span class = "plain" > ));< / span >
< span class = "identifier" > found< / span > < span class = "plain" > = < / span > < span class = "constant" > TRUE< / span > < span class = "plain" > ;< / span >
< span class = "plain" > }< / span >
< span class = "identifier" > DISCARD_TEXT< / span > < span class = "plain" > (< / span > < span class = "identifier" > QT< / span > < span class = "plain" > );< / span >
< span class = "identifier" > q_up_count< / span > < span class = "plain" > ++;< / span >
< span class = "plain" > }< / span >
< span class = "identifier" > DISCARD_TEXT< / span > < span class = "plain" > (< / span > < span class = "identifier" > PT< / span > < span class = "plain" > );< / span >
< span class = "plain" > }< / span >
< span class = "reserved" > if< / span > < span class = "plain" > (< / span > < span class = "identifier" > found< / span > < span class = "plain" > == < / span > < span class = "constant" > FALSE< / span > < span class = "plain" > ) < / span > < span class = "identifier" > internal_error< / span > < span class = "plain" > (< / span > < span class = "string" > "no relation made"< / span > < span class = "plain" > );< / span >
< span class = "reserved" > if< / span > < span class = "plain" > (< / span > < span class = "functiontext" > < a href = "4-sm.html#SP8" > Str::len< / a > < / span > < span class = "plain" > (< / span > < span class = "identifier" > OUT< / span > < span class = "plain" > ) > < / span > < span class = "constant" > 0< / span > < span class = "plain" > ) < / span > < span class = "identifier" > WRITE< / span > < span class = "plain" > (< / span > < span class = "string" > "/"< / span > < span class = "plain" > );< / span >
< span class = "plain" > }< / span >
< / pre >
< p class = "inwebparagraph" > < / p >
< p class = "inwebparagraph" > < a id = "SP9" > < / a > < b > § 9. Existence in the file system. < / b > Just because we have a pathname, it doesn't follow that any folder exists
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on the file system with that path.
< / p >
< pre class = "display" >
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< span class = "reserved" > int< / span > < span class = "plain" > < / span > < span class = "functiontext" > Pathnames::create_in_file_system< button class = "popup" onclick = "togglePopup('usagePopup202')" > ...< span class = "popuptext" id = "usagePopup202" > Usage of < b > Pathnames::create_in_file_system< / b > :< br > Epub Ebooks - < a href = "5-ee.html#SP6" > § 6< / a > , < a href = "5-ee.html#SP6_2" > § 6.2< / a > < / span > < / button > < / span > < span class = "plain" > (< / span > < span class = "reserved" > pathname< / span > < span class = "plain" > *< / span > < span class = "identifier" > P< / span > < span class = "plain" > ) {< / span >
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< span class = "reserved" > if< / span > < span class = "plain" > (< / span > < span class = "identifier" > P< / span > < span class = "plain" > == < / span > < span class = "identifier" > NULL< / span > < span class = "plain" > ) < / span > < span class = "reserved" > return< / span > < span class = "plain" > < / span > < span class = "constant" > TRUE< / span > < span class = "plain" > ; < / span > < span class = "comment" > the root of the file system always exists< / span >
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< span class = "reserved" > if< / span > < span class = "plain" > (< / span > < span class = "identifier" > P< / span > < span class = "plain" > -> < / span > < span class = "element" > known_to_exist< / span > < span class = "plain" > ) < / span > < span class = "reserved" > return< / span > < span class = "plain" > < / span > < span class = "constant" > TRUE< / span > < span class = "plain" > ;< / span >
< span class = "reserved" > char< / span > < span class = "plain" > < / span > < span class = "identifier" > transcoded_pathname< / span > < span class = "plain" > [4*< / span > < span class = "constant" > MAX_FILENAME_LENGTH< / span > < span class = "plain" > ];< / span >
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< span class = "identifier" > TEMPORARY_TEXT< / span > < span class = "plain" > (< / span > < span class = "identifier" > pn< / span > < span class = "plain" > );< / span >
< span class = "identifier" > WRITE_TO< / span > < span class = "plain" > (< / span > < span class = "identifier" > pn< / span > < span class = "plain" > , < / span > < span class = "string" > "%p"< / span > < span class = "plain" > , < / span > < span class = "identifier" > P< / span > < span class = "plain" > );< / span >
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< span class = "functiontext" > < a href = "4-sm.html#SP6" > Str::copy_to_locale_string< / a > < / span > < span class = "plain" > (< / span > < span class = "identifier" > transcoded_pathname< / span > < span class = "plain" > , < / span > < span class = "identifier" > pn< / span > < span class = "plain" > , < / span > < span class = "constant" > 4< / span > < span class = "plain" > *< / span > < span class = "constant" > MAX_FILENAME_LENGTH< / span > < span class = "plain" > );< / span >
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< span class = "identifier" > DISCARD_TEXT< / span > < span class = "plain" > (< / span > < span class = "identifier" > pn< / span > < span class = "plain" > );< / span >
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< span class = "identifier" > P< / span > < span class = "plain" > -> < / span > < span class = "element" > known_to_exist< / span > < span class = "plain" > = < / span > < span class = "functiontext" > < a href = "1-wp.html#SP7" > Platform::mkdir< / a > < / span > < span class = "plain" > (< / span > < span class = "identifier" > transcoded_pathname< / span > < span class = "plain" > );< / span >
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< span class = "reserved" > return< / span > < span class = "plain" > < / span > < span class = "identifier" > P< / span > < span class = "plain" > -> < / span > < span class = "identifier" > known_to_exist< / span > < span class = "plain" > ;< / span >
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< span class = "plain" > }< / span >
< / pre >
< p class = "inwebparagraph" > < / p >
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< p class = "inwebparagraph" > < a id = "SP10" > < / a > < b > § 10. Directory synchronisation. < / b > Both pathnames here represent directories which do exist. The function makes
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the < code class = "display" > < span class = "extract" > dest< / span > < / code > tree an exact copy of the < code class = "display" > < span class = "extract" > source< / span > < / code > tree (and therefore deletes
anything different which was originally in < code class = "display" > < span class = "extract" > dest< / span > < / code > ).
< / p >
< pre class = "display" >
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< span class = "reserved" > void< / span > < span class = "plain" > < / span > < span class = "functiontext" > Pathnames::rsync< button class = "popup" onclick = "togglePopup('usagePopup203')" > ...< span class = "popuptext" id = "usagePopup203" > Usage of < b > Pathnames::rsync< / b > :< br > none< / span > < / button > < / span > < span class = "plain" > (< / span > < span class = "reserved" > pathname< / span > < span class = "plain" > *< / span > < span class = "identifier" > source< / span > < span class = "plain" > , < / span > < span class = "reserved" > pathname< / span > < span class = "plain" > *< / span > < span class = "identifier" > dest< / span > < span class = "plain" > ) {< / span >
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< span class = "reserved" > char< / span > < span class = "plain" > < / span > < span class = "identifier" > transcoded_source< / span > < span class = "plain" > [4*< / span > < span class = "constant" > MAX_FILENAME_LENGTH< / span > < span class = "plain" > ];< / span >
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< span class = "identifier" > TEMPORARY_TEXT< / span > < span class = "plain" > (< / span > < span class = "identifier" > pn< / span > < span class = "plain" > );< / span >
< span class = "identifier" > WRITE_TO< / span > < span class = "plain" > (< / span > < span class = "identifier" > pn< / span > < span class = "plain" > , < / span > < span class = "string" > "%p"< / span > < span class = "plain" > , < / span > < span class = "identifier" > source< / span > < span class = "plain" > );< / span >
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< span class = "functiontext" > < a href = "4-sm.html#SP6" > Str::copy_to_locale_string< / a > < / span > < span class = "plain" > (< / span > < span class = "identifier" > transcoded_source< / span > < span class = "plain" > , < / span > < span class = "identifier" > pn< / span > < span class = "plain" > , < / span > < span class = "constant" > 4< / span > < span class = "plain" > *< / span > < span class = "constant" > MAX_FILENAME_LENGTH< / span > < span class = "plain" > );< / span >
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< span class = "identifier" > DISCARD_TEXT< / span > < span class = "plain" > (< / span > < span class = "identifier" > pn< / span > < span class = "plain" > );< / span >
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< span class = "reserved" > char< / span > < span class = "plain" > < / span > < span class = "identifier" > transcoded_dest< / span > < span class = "plain" > [4*< / span > < span class = "constant" > MAX_FILENAME_LENGTH< / span > < span class = "plain" > ];< / span >
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< span class = "identifier" > TEMPORARY_TEXT< / span > < span class = "plain" > (< / span > < span class = "identifier" > pn2< / span > < span class = "plain" > );< / span >
< span class = "identifier" > WRITE_TO< / span > < span class = "plain" > (< / span > < span class = "identifier" > pn2< / span > < span class = "plain" > , < / span > < span class = "string" > "%p"< / span > < span class = "plain" > , < / span > < span class = "identifier" > dest< / span > < span class = "plain" > );< / span >
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< span class = "functiontext" > < a href = "4-sm.html#SP6" > Str::copy_to_locale_string< / a > < / span > < span class = "plain" > (< / span > < span class = "identifier" > transcoded_dest< / span > < span class = "plain" > , < / span > < span class = "identifier" > pn2< / span > < span class = "plain" > , < / span > < span class = "constant" > 4< / span > < span class = "plain" > *< / span > < span class = "constant" > MAX_FILENAME_LENGTH< / span > < span class = "plain" > );< / span >
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< span class = "identifier" > DISCARD_TEXT< / span > < span class = "plain" > (< / span > < span class = "identifier" > pn2< / span > < span class = "plain" > );< / span >
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< span class = "functiontext" > < a href = "1-pp.html#SP14" > Platform::rsync< / a > < / span > < span class = "plain" > (< / span > < span class = "identifier" > transcoded_source< / span > < span class = "plain" > , < / span > < span class = "identifier" > transcoded_dest< / span > < span class = "plain" > );< / span >
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< span class = "plain" > }< / span >
< / pre >
< p class = "inwebparagraph" > < / p >
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< hr class = "tocbar" >
< ul class = "toc" > < li > < a href = "3-cla.html" > Back to 'Command Line Arguments'< / a > < / li > < li > < a href = "3-fln.html" > Continue with 'Filenames'< / a > < / li > < / ul > < hr class = "tocbar" >
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<!-- End of weave -->
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< script >
function togglePopup(material_id) {
var popup = document.getElementById(material_id);
popup.classList.toggle("show");
}
< / script >
< link href = "Popups.css" rel = "stylesheet" rev = "stylesheet" type = "text/css" >
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< / main >
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< / body >
< / html >
