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< h2 > Foundation< / h2 >
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<!-- Weave of '3/em' generated by 7 -->
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< ul class = "crumbs" > < li > < a href = "../webs.html" > Source< / 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 > Error Messages< / b > < / li > < / ul > < p class = "purpose" > A basic system for command-line tool error messages.< / p >
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< ul class = "toc" > < li > < a href = "#SP1" > § 1. Errors handler< / a > < / li > < li > < a href = "#SP2" > § 2. Error messages< / a > < / li > < li > < a href = "#SP4" > § 4. Deliberately crashing< / a > < / li > < li > < a href = "#SP5" > § 5. Survivable errors< / a > < / li > < / ul > < hr class = "tocbar" >
< p class = "inwebparagraph" > < a id = "SP1" > < / a > < b > § 1. Errors handler. < / b > The user can provide a routine to deal with error messages before they're
issued. If this returns < code class = "display" > < span class = "extract" > FALSE< / span > < / code > , nothing is printed to < code class = "display" > < span class = "extract" > stderr< / span > < / code > .
< / p >
< pre class = "display" >
< span class = "reserved" > int< / span > < span class = "plain" > (*< / span > < span class = "identifier" > errors_handler< / span > < span class = "plain" > )(< / span > < span class = "reserved" > text_stream< / span > < span class = "plain" > *, < / span > < span class = "reserved" > int< / 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 = "identifier" > internal_errors_handler< / 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 = "reserved" > char< / span > < span class = "plain" > *, < / span > < span class = "reserved" > int< / 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" > Errors::set_handler< / span > < span class = "plain" > (< / span > < span class = "reserved" > int< / span > < span class = "plain" > (*< / span > < span class = "identifier" > f< / span > < span class = "plain" > )(< / span > < span class = "reserved" > text_stream< / span > < span class = "plain" > *, < / span > < span class = "reserved" > int< / span > < span class = "plain" > )) {< / span >
< span class = "identifier" > errors_handler< / span > < span class = "plain" > = < / span > < span class = "identifier" > f< / span > < span class = "plain" > ;< / span >
< span class = "plain" > }< / span >
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< span class = "reserved" > void< / span > < span class = "plain" > < / span > < span class = "functiontext" > Errors::set_internal_handler< / span > < span class = "plain" > (< / span > < span class = "reserved" > void< / span > < span class = "plain" > (*< / span > < span class = "identifier" > f< / 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 = "reserved" > char< / span > < span class = "plain" > *, < / span > < span class = "reserved" > int< / span > < span class = "plain" > )) {< / span >
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< span class = "identifier" > internal_errors_handler< / span > < span class = "plain" > = < / span > < span class = "identifier" > f< / span > < span class = "plain" > ;< / span >
< span class = "plain" > }< / span >
< span class = "reserved" > int< / span > < span class = "plain" > < / span > < span class = "identifier" > problem_count< / span > < span class = "plain" > = 0;< / span >
< span class = "reserved" > int< / span > < span class = "plain" > < / span > < span class = "functiontext" > Errors::have_occurred< / span > < span class = "plain" > (< / span > < span class = "reserved" > void< / span > < span class = "plain" > ) {< / span >
< span class = "reserved" > if< / span > < span class = "plain" > (< / span > < span class = "identifier" > problem_count< / span > < span class = "plain" > > 0) < / span > < span class = "reserved" > return< / span > < span class = "plain" > < / span > < span class = "constant" > TRUE< / span > < span class = "plain" > ;< / span >
< span class = "reserved" > return< / span > < span class = "plain" > < / span > < span class = "constant" > FALSE< / span > < span class = "plain" > ;< / span >
< span class = "plain" > }< / span >
< span class = "reserved" > void< / span > < span class = "plain" > < / span > < span class = "functiontext" > Errors::issue< / span > < span class = "plain" > (< / span > < span class = "reserved" > text_stream< / span > < span class = "plain" > *< / span > < span class = "identifier" > message< / span > < span class = "plain" > , < / span > < span class = "reserved" > int< / span > < span class = "plain" > < / span > < span class = "identifier" > fatality< / span > < span class = "plain" > ) {< / span >
< span class = "reserved" > int< / span > < span class = "plain" > < / span > < span class = "identifier" > rv< / span > < span class = "plain" > = < / span > < span class = "constant" > TRUE< / span > < span class = "plain" > ;< / span >
< span class = "reserved" > if< / span > < span class = "plain" > (< / span > < span class = "identifier" > errors_handler< / span > < span class = "plain" > ) < / span > < span class = "identifier" > rv< / span > < span class = "plain" > = (*< / span > < span class = "identifier" > errors_handler< / span > < span class = "plain" > )(< / span > < span class = "identifier" > message< / span > < span class = "plain" > , < / span > < span class = "identifier" > fatality< / span > < span class = "plain" > );< / span >
< span class = "reserved" > if< / span > < span class = "plain" > (< / span > < span class = "identifier" > rv< / span > < span class = "plain" > ) < / span > < span class = "identifier" > WRITE_TO< / span > < span class = "plain" > (< / span > < span class = "constant" > STDERR< / span > < span class = "plain" > , < / span > < span class = "string" > "%S"< / span > < span class = "plain" > , < / span > < span class = "identifier" > message< / span > < span class = "plain" > );< / span >
< span class = "reserved" > if< / span > < span class = "plain" > (< / span > < span class = "identifier" > fatality< / span > < span class = "plain" > ) < / span > < span class = "functiontext" > Errors::die< / span > < span class = "plain" > (); < / span > < span class = "reserved" > else< / span > < span class = "plain" > < / span > < span class = "identifier" > problem_count< / span > < span class = "plain" > ++;< / span >
< span class = "plain" > }< / span >
< / pre >
< p class = "inwebparagraph" > < / p >
< p class = "endnote" > The function Errors::set_handler appears nowhere else.< / p >
< p class = "endnote" > The function Errors::set_internal_handler appears nowhere else.< / p >
< p class = "endnote" > The function Errors::have_occurred is used in 2/str (< a href = "2-str.html#SP37" > § 37< / a > ).< / p >
< p class = "endnote" > The function Errors::issue is used in < a href = "#SP2" > § 2< / a > , < a href = "#SP6" > § 6< / a > , < a href = "#SP7" > § 7< / a > .< / p >
< p class = "inwebparagraph" > < a id = "SP2" > < / a > < b > § 2. Error messages. < / b > Ah, they kill you; or they don't. The fatal kind cause an exit code of 2, to
distinguish this from a proper completion in which non-fatal errors occur.
These two routines (alone) can be caused by failures of the memory allocation
or streams systems, and therefore must be written with a little care to use
the temporary stream, not some other string which might need fresh allocation.
< / p >
< pre class = "display" >
< span class = "reserved" > void< / span > < span class = "plain" > < / span > < span class = "functiontext" > Errors::fatal< / span > < span class = "plain" > (< / span > < span class = "reserved" > char< / span > < span class = "plain" > *< / span > < span class = "identifier" > message< / span > < span class = "plain" > ) {< / span >
< span class = "identifier" > TEMPORARY_TEXT< / span > < span class = "plain" > (< / span > < span class = "identifier" > ERM< / span > < span class = "plain" > )< / span >
< span class = "identifier" > WRITE_TO< / span > < span class = "plain" > (< / span > < span class = "identifier" > ERM< / span > < span class = "plain" > , < / span > < span class = "string" > "%s: fatal error: %s\< / span > < span class = "plain" > n< / span > < span class = "string" > "< / span > < span class = "plain" > , < / span > < span class = "identifier" > INTOOL_NAME< / span > < span class = "plain" > , < / span > < span class = "identifier" > message< / span > < span class = "plain" > );< / span >
< span class = "functiontext" > Errors::issue< / span > < span class = "plain" > (< / span > < span class = "identifier" > ERM< / span > < span class = "plain" > , < / span > < span class = "constant" > TRUE< / span > < span class = "plain" > );< / span >
< span class = "identifier" > DISCARD_TEXT< / span > < span class = "plain" > (< / span > < span class = "identifier" > ERM< / span > < span class = "plain" > )< / span >
< span class = "plain" > }< / span >
< span class = "reserved" > void< / span > < span class = "plain" > < / span > < span class = "functiontext" > Errors::fatal_with_C_string< / span > < span class = "plain" > (< / span > < span class = "reserved" > char< / span > < span class = "plain" > *< / span > < span class = "identifier" > message< / span > < span class = "plain" > , < / span > < span class = "reserved" > char< / span > < span class = "plain" > *< / span > < span class = "identifier" > parameter< / span > < span class = "plain" > ) {< / span >
< span class = "identifier" > TEMPORARY_TEXT< / span > < span class = "plain" > (< / span > < span class = "identifier" > ERM< / span > < span class = "plain" > )< / span >
< span class = "identifier" > WRITE_TO< / span > < span class = "plain" > (< / span > < span class = "identifier" > ERM< / span > < span class = "plain" > , < / span > < span class = "string" > "%s: fatal error: "< / span > < span class = "plain" > , < / span > < span class = "identifier" > INTOOL_NAME< / span > < span class = "plain" > );< / span >
< span class = "identifier" > WRITE_TO< / span > < span class = "plain" > (< / span > < span class = "identifier" > ERM< / span > < span class = "plain" > , < / span > < span class = "identifier" > message< / span > < span class = "plain" > , < / span > < span class = "identifier" > parameter< / span > < span class = "plain" > );< / span >
< span class = "identifier" > WRITE_TO< / span > < span class = "plain" > (< / span > < span class = "identifier" > ERM< / span > < span class = "plain" > , < / span > < span class = "string" > "\< / span > < span class = "plain" > n< / span > < span class = "string" > "< / span > < span class = "plain" > );< / span >
< span class = "functiontext" > Errors::issue< / span > < span class = "plain" > (< / span > < span class = "identifier" > ERM< / span > < span class = "plain" > , < / span > < span class = "constant" > TRUE< / span > < span class = "plain" > );< / span >
< span class = "identifier" > DISCARD_TEXT< / span > < span class = "plain" > (< / span > < span class = "identifier" > ERM< / span > < span class = "plain" > )< / span >
< span class = "plain" > }< / span >
< span class = "reserved" > void< / span > < span class = "plain" > < / span > < span class = "functiontext" > Errors::fatal_with_text< / span > < span class = "plain" > (< / span > < span class = "reserved" > char< / span > < span class = "plain" > *< / span > < span class = "identifier" > message< / span > < span class = "plain" > , < / span > < span class = "reserved" > text_stream< / span > < span class = "plain" > *< / span > < span class = "identifier" > parameter< / span > < span class = "plain" > ) {< / span >
< span class = "identifier" > TEMPORARY_TEXT< / span > < span class = "plain" > (< / span > < span class = "identifier" > ERM< / span > < span class = "plain" > )< / span >
< span class = "identifier" > WRITE_TO< / span > < span class = "plain" > (< / span > < span class = "identifier" > ERM< / span > < span class = "plain" > , < / span > < span class = "string" > "%s: fatal error: "< / span > < span class = "plain" > , < / span > < span class = "identifier" > INTOOL_NAME< / span > < span class = "plain" > );< / span >
< span class = "identifier" > WRITE_TO< / span > < span class = "plain" > (< / span > < span class = "identifier" > ERM< / span > < span class = "plain" > , < / span > < span class = "identifier" > message< / span > < span class = "plain" > , < / span > < span class = "identifier" > parameter< / span > < span class = "plain" > );< / span >
< span class = "identifier" > WRITE_TO< / span > < span class = "plain" > (< / span > < span class = "identifier" > ERM< / span > < span class = "plain" > , < / span > < span class = "string" > "\< / span > < span class = "plain" > n< / span > < span class = "string" > "< / span > < span class = "plain" > );< / span >
< span class = "functiontext" > Errors::issue< / span > < span class = "plain" > (< / span > < span class = "identifier" > ERM< / span > < span class = "plain" > , < / span > < span class = "constant" > TRUE< / span > < span class = "plain" > );< / span >
< span class = "identifier" > DISCARD_TEXT< / span > < span class = "plain" > (< / span > < span class = "identifier" > ERM< / span > < span class = "plain" > )< / span >
< span class = "plain" > }< / span >
< span class = "reserved" > void< / span > < span class = "plain" > < / span > < span class = "functiontext" > Errors::fatal_with_file< / span > < span class = "plain" > (< / span > < span class = "reserved" > char< / span > < span class = "plain" > *< / span > < span class = "identifier" > message< / 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 = "identifier" > TEMPORARY_TEXT< / span > < span class = "plain" > (< / span > < span class = "identifier" > ERM< / span > < span class = "plain" > )< / span >
< span class = "identifier" > WRITE_TO< / span > < span class = "plain" > (< / span > < span class = "identifier" > ERM< / span > < span class = "plain" > , < / span > < span class = "string" > "%s: fatal error: %s: %f\< / span > < span class = "plain" > n< / span > < span class = "string" > "< / span > < span class = "plain" > , < / span > < span class = "identifier" > INTOOL_NAME< / span > < span class = "plain" > , < / span > < span class = "identifier" > message< / span > < span class = "plain" > , < / span > < span class = "identifier" > F< / span > < span class = "plain" > );< / span >
< span class = "functiontext" > Errors::issue< / span > < span class = "plain" > (< / span > < span class = "identifier" > ERM< / span > < span class = "plain" > , < / span > < span class = "constant" > TRUE< / span > < span class = "plain" > );< / span >
< span class = "identifier" > DISCARD_TEXT< / span > < span class = "plain" > (< / span > < span class = "identifier" > ERM< / span > < span class = "plain" > )< / span >
< span class = "plain" > }< / span >
< span class = "reserved" > void< / span > < span class = "plain" > < / span > < span class = "functiontext" > Errors::fatal_with_path< / span > < span class = "plain" > (< / span > < span class = "reserved" > char< / span > < span class = "plain" > *< / span > < span class = "identifier" > message< / 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" > TEMPORARY_TEXT< / span > < span class = "plain" > (< / span > < span class = "identifier" > ERM< / span > < span class = "plain" > )< / span >
< span class = "identifier" > WRITE_TO< / span > < span class = "plain" > (< / span > < span class = "identifier" > ERM< / span > < span class = "plain" > , < / span > < span class = "string" > "%s: fatal error: %s: %p\< / span > < span class = "plain" > n< / span > < span class = "string" > "< / span > < span class = "plain" > , < / span > < span class = "identifier" > INTOOL_NAME< / span > < span class = "plain" > , < / span > < span class = "identifier" > message< / span > < span class = "plain" > , < / span > < span class = "identifier" > P< / span > < span class = "plain" > );< / span >
< span class = "functiontext" > Errors::issue< / span > < span class = "plain" > (< / span > < span class = "identifier" > ERM< / span > < span class = "plain" > , < / span > < span class = "constant" > TRUE< / span > < span class = "plain" > );< / span >
< span class = "identifier" > DISCARD_TEXT< / span > < span class = "plain" > (< / span > < span class = "identifier" > ERM< / span > < span class = "plain" > )< / span >
< span class = "plain" > }< / span >
< / pre >
< p class = "inwebparagraph" > < / p >
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< p class = "endnote" > The function Errors::fatal is used in 2/mmr (< a href = "2-mmr.html#SP11_1" > § 11.1< / a > , < a href = "2-mmr.html#SP15" > § 15< / a > , < a href = "2-mmr.html#SP16_1" > § 16.1< / a > ), 2/str (< a href = "2-str.html#SP34_1" > § 34.1< / a > , < a href = "2-str.html#SP35_3" > § 35.3< / a > ), 4/cst (< a href = "4-cst.html#SP3" > § 3< / a > ), 6/bf (< a href = "6-bf.html#SP9" > § 9< / a > ), 8/bf (< a href = "8-bf.html#SP7" > § 7< / a > ).< / p >
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< p class = "endnote" > The function Errors::fatal_with_C_string is used in < a href = "#SP3" > § 3< / a > , 2/mmr (< a href = "2-mmr.html#SP26_1" > § 26.1< / a > ).< / p >
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< p class = "endnote" > The function Errors::fatal_with_text is used in 3/cla (< a href = "3-cla.html#SP8" > § 8< / a > , < a href = "3-cla.html#SP11" > § 11< / a > , < a href = "3-cla.html#SP13" > § 13< / a > ), 8/bdfw (< a href = "8-bdfw.html#SP5" > § 5< / a > ), 8/bf (< a href = "8-bf.html#SP6" > § 6< / a > ).< / p >
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< p class = "endnote" > The function Errors::fatal_with_file is used in 4/tf (< a href = "4-tf.html#SP5_1" > § 5.1< / a > , < a href = "4-tf.html#SP5_2" > § 5.2< / a > , < a href = "4-tf.html#SP5_3_2" > § 5.3.2< / a > ), 5/ee (< a href = "5-ee.html#SP6_1" > § 6.1< / a > , < a href = "5-ee.html#SP6_2" > § 6.2< / a > , < a href = "5-ee.html#SP6_3" > § 6.3< / a > , < a href = "5-ee.html#SP7_2" > § 7.2< / a > , < a href = "5-ee.html#SP7_3" > § 7.3< / a > ), 6/bf (< a href = "6-bf.html#SP7" > § 7< / a > , < a href = "6-bf.html#SP8" > § 8< / a > , < a href = "6-bf.html#SP9" > § 9< / a > ), 8/bf (< a href = "8-bf.html#SP4" > § 4< / a > ).< / p >
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< p class = "endnote" > The function Errors::fatal_with_path appears nowhere else.< / p >
< p class = "inwebparagraph" > < a id = "SP3" > < / a > < b > § 3. < / b > Assertion failures lead to the following:
< / p >
< pre class = "definitions" >
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< span class = "definitionkeyword" > define< / span > < span class = "identifier" > internal_error< / span > < span class = "plain" > (< / span > < span class = "identifier" > message< / span > < span class = "plain" > ) < / span > < span class = "functiontext" > Errors::internal_error_handler< / span > < span class = "plain" > (< / span > < span class = "identifier" > NULL< / span > < span class = "plain" > , < / span > < span class = "identifier" > message< / span > < span class = "plain" > , < / span > < span class = "identifier" > __FILE__< / span > < span class = "plain" > , < / span > < span class = "identifier" > __LINE__< / span > < span class = "plain" > )< / span >
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< / pre >
< pre class = "display" >
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< span class = "reserved" > void< / span > < span class = "plain" > < / span > < span class = "functiontext" > Errors::internal_error_handler< / span > < span class = "plain" > (< / span > < span class = "reserved" > void< / span > < span class = "plain" > *< / span > < span class = "identifier" > p< / span > < span class = "plain" > , < / span > < span class = "reserved" > char< / span > < span class = "plain" > *< / span > < span class = "identifier" > message< / span > < span class = "plain" > , < / span > < span class = "reserved" > char< / span > < span class = "plain" > *< / span > < span class = "identifier" > f< / span > < span class = "plain" > , < / span > < span class = "reserved" > int< / span > < span class = "plain" > < / span > < span class = "identifier" > lc< / span > < span class = "plain" > ) {< / span >
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< span class = "reserved" > if< / span > < span class = "plain" > (< / span > < span class = "identifier" > internal_errors_handler< / span > < span class = "plain" > )< / span >
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< span class = "plain" > (*< / span > < span class = "identifier" > internal_errors_handler< / span > < span class = "plain" > )(< / span > < span class = "identifier" > p< / span > < span class = "plain" > , < / span > < span class = "identifier" > message< / span > < span class = "plain" > , < / span > < span class = "identifier" > f< / span > < span class = "plain" > , < / span > < span class = "identifier" > lc< / span > < span class = "plain" > );< / span >
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< span class = "reserved" > else< / span >
< span class = "functiontext" > Errors::fatal_with_C_string< / span > < span class = "plain" > (< / span > < span class = "string" > "internal error (%s)"< / span > < span class = "plain" > , < / span > < span class = "identifier" > message< / span > < span class = "plain" > );< / span >
< span class = "plain" > }< / span >
< / pre >
< p class = "inwebparagraph" > < / p >
< p class = "endnote" > The function Errors::internal_error_handler appears nowhere else.< / p >
< p class = "inwebparagraph" > < a id = "SP4" > < / a > < b > § 4. Deliberately crashing. < / b > It's sometimes convenient to get a backtrace from the debugger when an error
occurs unexpectedly, and one way to do that is to force a division by zero.
(This is only enabled by < code class = "display" > < span class = "extract" > -crash< / span > < / code > at the command line and is for debugging only.)
< / p >
< pre class = "display" >
< span class = "reserved" > int< / span > < span class = "plain" > < / span > < span class = "identifier" > debugger_mode< / span > < span class = "plain" > = < / span > < span class = "constant" > FALSE< / span > < span class = "plain" > ;< / span >
< span class = "reserved" > void< / span > < span class = "plain" > < / span > < span class = "functiontext" > Errors::enter_debugger_mode< / span > < span class = "plain" > (< / span > < span class = "reserved" > void< / span > < span class = "plain" > ) {< / span >
< span class = "identifier" > debugger_mode< / span > < span class = "plain" > = < / span > < span class = "constant" > TRUE< / span > < span class = "plain" > ;< / span >
< span class = "identifier" > printf< / span > < span class = "plain" > (< / span > < span class = "string" > "(Debugger mode enabled: will crash on fatal errors)\< / span > < span class = "plain" > n< / span > < span class = "string" > "< / span > < span class = "plain" > );< / span >
< span class = "plain" > }< / span >
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< span class = "reserved" > void< / span > < span class = "plain" > < / span > < span class = "functiontext" > Errors::die< / span > < span class = "plain" > (< / span > < span class = "reserved" > void< / span > < span class = "plain" > ) { < / span > < span class = "comment" > as void as it gets< / span >
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< span class = "reserved" > if< / span > < span class = "plain" > (< / span > < span class = "identifier" > DL< / span > < span class = "plain" > ) < / span > < span class = "identifier" > STREAM_FLUSH< / span > < span class = "plain" > (< / span > < span class = "identifier" > DL< / span > < span class = "plain" > );< / span >
< span class = "reserved" > if< / span > < span class = "plain" > (< / span > < span class = "identifier" > debugger_mode< / span > < span class = "plain" > ) {< / span >
< span class = "identifier" > WRITE_TO< / span > < span class = "plain" > (< / span > < span class = "constant" > STDERR< / span > < span class = "plain" > , < / span > < span class = "string" > "(crashing intentionally to allow backtrace)\< / span > < span class = "plain" > n< / span > < span class = "string" > "< / span > < span class = "plain" > );< / span >
< span class = "reserved" > int< / span > < span class = "plain" > < / span > < span class = "identifier" > to_deliberately_crash< / span > < span class = "plain" > = 0;< / span >
< span class = "identifier" > printf< / span > < span class = "plain" > (< / span > < span class = "string" > "%d"< / span > < span class = "plain" > , 1/< / span > < span class = "identifier" > to_deliberately_crash< / span > < span class = "plain" > );< / span >
< span class = "plain" > }< / span >
< span class = "comment" > on a fatal exit, memory isn't freed, because that causes threading problems< / span >
< span class = "identifier" > exit< / span > < span class = "plain" > (2);< / span >
< span class = "plain" > }< / span >
< / pre >
< p class = "inwebparagraph" > < / p >
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< p class = "endnote" > The function Errors::enter_debugger_mode is used in 3/cla (< a href = "3-cla.html#SP13_1" > § 13.1< / a > ).< / p >
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< p class = "endnote" > The function Errors::die is used in < a href = "#SP1" > § 1< / a > .< / p >
< p class = "inwebparagraph" > < a id = "SP5" > < / a > < b > § 5. Survivable errors. < / b > The trick with error messages is to indicate where they occur, and we can
specify this at three levels of abstraction:
< / p >
< pre class = "display" >
< span class = "reserved" > void< / span > < span class = "plain" > < / span > < span class = "functiontext" > Errors::nowhere< / span > < span class = "plain" > (< / span > < span class = "reserved" > char< / span > < span class = "plain" > *< / span > < span class = "identifier" > message< / span > < span class = "plain" > ) {< / span >
< span class = "functiontext" > Errors::in_text_file< / span > < span class = "plain" > (< / span > < span class = "identifier" > message< / span > < span class = "plain" > , < / span > < span class = "identifier" > NULL< / span > < span class = "plain" > );< / span >
< span class = "plain" > }< / span >
< span class = "reserved" > void< / span > < span class = "plain" > < / span > < span class = "functiontext" > Errors::in_text_file< / span > < span class = "plain" > (< / span > < span class = "reserved" > char< / span > < span class = "plain" > *< / span > < span class = "identifier" > message< / span > < span class = "plain" > , < / span > < span class = "reserved" > text_file_position< / span > < span class = "plain" > *< / span > < span class = "identifier" > here< / span > < span class = "plain" > ) {< / span >
< span class = "reserved" > if< / span > < span class = "plain" > (< / span > < span class = "identifier" > here< / span > < span class = "plain" > )< / span >
< span class = "functiontext" > Errors::at_position< / span > < span class = "plain" > (< / span > < span class = "identifier" > message< / span > < span class = "plain" > , < / span > < span class = "identifier" > here< / span > < span class = "plain" > -< / span > < span class = "element" > > text_file_filename< / span > < span class = "plain" > , < / span > < span class = "identifier" > here< / span > < span class = "plain" > -< / span > < span class = "element" > > line_count< / span > < span class = "plain" > );< / span >
< span class = "reserved" > else< / span >
< span class = "functiontext" > Errors::at_position< / span > < span class = "plain" > (< / span > < span class = "identifier" > message< / span > < span class = "plain" > , < / span > < span class = "identifier" > NULL< / span > < span class = "plain" > , 0);< / span >
< span class = "plain" > }< / span >
< span class = "reserved" > void< / span > < span class = "plain" > < / span > < span class = "functiontext" > Errors::in_text_file_S< / span > < span class = "plain" > (< / span > < span class = "reserved" > text_stream< / span > < span class = "plain" > *< / span > < span class = "identifier" > message< / span > < span class = "plain" > , < / span > < span class = "reserved" > text_file_position< / span > < span class = "plain" > *< / span > < span class = "identifier" > here< / span > < span class = "plain" > ) {< / span >
< span class = "reserved" > if< / span > < span class = "plain" > (< / span > < span class = "identifier" > here< / span > < span class = "plain" > )< / span >
< span class = "functiontext" > Errors::at_position_S< / span > < span class = "plain" > (< / span > < span class = "identifier" > message< / span > < span class = "plain" > , < / span > < span class = "identifier" > here< / span > < span class = "plain" > -< / span > < span class = "element" > > text_file_filename< / span > < span class = "plain" > , < / span > < span class = "identifier" > here< / span > < span class = "plain" > -< / span > < span class = "element" > > line_count< / span > < span class = "plain" > );< / span >
< span class = "reserved" > else< / span >
< span class = "functiontext" > Errors::at_position_S< / span > < span class = "plain" > (< / span > < span class = "identifier" > message< / span > < span class = "plain" > , < / span > < span class = "identifier" > NULL< / span > < span class = "plain" > , 0);< / span >
< span class = "plain" > }< / span >
< / pre >
< p class = "inwebparagraph" > < / p >
< p class = "endnote" > The function Errors::nowhere is used in 5/ee (< a href = "5-ee.html#SP7_2_2_3" > § 7.2.2.3< / a > ).< / p >
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< p class = "endnote" > The function Errors::in_text_file is used in 3/cla (< a href = "3-cla.html#SP11" > § 11< / a > ), 8/bf (< a href = "8-bf.html#SP3" > § 3< / a > ).< / p >
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< p class = "endnote" > The function Errors::in_text_file_S is used in 8/ws (< a href = "8-ws.html#SP7_3_2" > § 7.3.2< / a > , < a href = "8-ws.html#SP7_3_2_1" > § 7.3.2.1< / a > , < a href = "8-ws.html#SP7_3_3_2" > § 7.3.3.2< / a > ).< / p >
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< p class = "inwebparagraph" > < a id = "SP6" > < / a > < b > § 6. < / b > Which funnel through:
< / p >
< pre class = "display" >
< span class = "reserved" > void< / span > < span class = "plain" > < / span > < span class = "functiontext" > Errors::at_position< / span > < span class = "plain" > (< / span > < span class = "reserved" > char< / span > < span class = "plain" > *< / span > < span class = "identifier" > message< / span > < span class = "plain" > , < / span > < span class = "reserved" > filename< / span > < span class = "plain" > *< / span > < span class = "identifier" > file< / span > < span class = "plain" > , < / span > < span class = "reserved" > int< / span > < span class = "plain" > < / span > < span class = "identifier" > line< / span > < span class = "plain" > ) {< / span >
< span class = "identifier" > TEMPORARY_TEXT< / span > < span class = "plain" > (< / span > < span class = "identifier" > ERM< / span > < span class = "plain" > )< / span >
< span class = "identifier" > WRITE_TO< / span > < span class = "plain" > (< / span > < span class = "identifier" > ERM< / span > < span class = "plain" > , < / span > < span class = "string" > "%s: "< / span > < span class = "plain" > , < / span > < span class = "identifier" > INTOOL_NAME< / span > < span class = "plain" > );< / span >
< span class = "reserved" > if< / span > < span class = "plain" > (< / span > < span class = "identifier" > file< / span > < span class = "plain" > ) < / span > < span class = "identifier" > WRITE_TO< / span > < span class = "plain" > (< / span > < span class = "identifier" > ERM< / span > < span class = "plain" > , < / span > < span class = "string" > "%f, line %d: "< / span > < span class = "plain" > , < / span > < span class = "identifier" > file< / span > < span class = "plain" > , < / span > < span class = "identifier" > line< / span > < span class = "plain" > );< / span >
< span class = "identifier" > WRITE_TO< / span > < span class = "plain" > (< / span > < span class = "identifier" > ERM< / span > < span class = "plain" > , < / span > < span class = "string" > "%s\< / span > < span class = "plain" > n< / span > < span class = "string" > "< / span > < span class = "plain" > , < / span > < span class = "identifier" > message< / span > < span class = "plain" > );< / span >
< span class = "functiontext" > Errors::issue< / span > < span class = "plain" > (< / span > < span class = "identifier" > ERM< / span > < span class = "plain" > , < / span > < span class = "constant" > FALSE< / span > < span class = "plain" > );< / span >
< span class = "identifier" > DISCARD_TEXT< / span > < span class = "plain" > (< / span > < span class = "identifier" > ERM< / span > < span class = "plain" > )< / span >
< span class = "plain" > }< / span >
< span class = "reserved" > void< / span > < span class = "plain" > < / span > < span class = "functiontext" > Errors::at_position_S< / span > < span class = "plain" > (< / span > < span class = "reserved" > text_stream< / span > < span class = "plain" > *< / span > < span class = "identifier" > message< / span > < span class = "plain" > , < / span > < span class = "reserved" > filename< / span > < span class = "plain" > *< / span > < span class = "identifier" > file< / span > < span class = "plain" > , < / span > < span class = "reserved" > int< / span > < span class = "plain" > < / span > < span class = "identifier" > line< / span > < span class = "plain" > ) {< / span >
< span class = "identifier" > TEMPORARY_TEXT< / span > < span class = "plain" > (< / span > < span class = "identifier" > ERM< / span > < span class = "plain" > )< / span >
< span class = "identifier" > WRITE_TO< / span > < span class = "plain" > (< / span > < span class = "identifier" > ERM< / span > < span class = "plain" > , < / span > < span class = "string" > "%s: "< / span > < span class = "plain" > , < / span > < span class = "identifier" > INTOOL_NAME< / span > < span class = "plain" > );< / span >
< span class = "reserved" > if< / span > < span class = "plain" > (< / span > < span class = "identifier" > file< / span > < span class = "plain" > ) < / span > < span class = "identifier" > WRITE_TO< / span > < span class = "plain" > (< / span > < span class = "identifier" > ERM< / span > < span class = "plain" > , < / span > < span class = "string" > "%f, line %d: "< / span > < span class = "plain" > , < / span > < span class = "identifier" > file< / span > < span class = "plain" > , < / span > < span class = "identifier" > line< / span > < span class = "plain" > );< / span >
< span class = "identifier" > WRITE_TO< / span > < span class = "plain" > (< / span > < span class = "identifier" > ERM< / span > < span class = "plain" > , < / span > < span class = "string" > "%S\< / span > < span class = "plain" > n< / span > < span class = "string" > "< / span > < span class = "plain" > , < / span > < span class = "identifier" > message< / span > < span class = "plain" > );< / span >
< span class = "functiontext" > Errors::issue< / span > < span class = "plain" > (< / span > < span class = "identifier" > ERM< / span > < span class = "plain" > , < / span > < span class = "constant" > FALSE< / span > < span class = "plain" > );< / span >
< span class = "identifier" > DISCARD_TEXT< / span > < span class = "plain" > (< / span > < span class = "identifier" > ERM< / span > < span class = "plain" > )< / span >
< span class = "plain" > }< / span >
< / pre >
< p class = "inwebparagraph" > < / p >
< p class = "endnote" > The function Errors::at_position is used in < a href = "#SP5" > § 5< / a > .< / p >
< p class = "endnote" > The function Errors::at_position_S is used in < a href = "#SP5" > § 5< / a > .< / p >
< p class = "inwebparagraph" > < a id = "SP7" > < / a > < b > § 7. < / b > Lastly:
< / p >
< pre class = "display" >
< span class = "reserved" > void< / span > < span class = "plain" > < / span > < span class = "functiontext" > Errors::with_file< / span > < span class = "plain" > (< / span > < span class = "reserved" > char< / span > < span class = "plain" > *< / span > < span class = "identifier" > message< / 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 = "identifier" > TEMPORARY_TEXT< / span > < span class = "plain" > (< / span > < span class = "identifier" > ERM< / span > < span class = "plain" > )< / span >
< span class = "identifier" > WRITE_TO< / span > < span class = "plain" > (< / span > < span class = "identifier" > ERM< / span > < span class = "plain" > , < / span > < span class = "string" > "%s: %f: %s\< / span > < span class = "plain" > n< / span > < span class = "string" > "< / span > < span class = "plain" > , < / span > < span class = "identifier" > INTOOL_NAME< / span > < span class = "plain" > , < / span > < span class = "identifier" > F< / span > < span class = "plain" > , < / span > < span class = "identifier" > message< / span > < span class = "plain" > );< / span >
< span class = "functiontext" > Errors::issue< / span > < span class = "plain" > (< / span > < span class = "identifier" > ERM< / span > < span class = "plain" > , < / span > < span class = "constant" > FALSE< / span > < span class = "plain" > );< / span >
< span class = "identifier" > DISCARD_TEXT< / span > < span class = "plain" > (< / span > < span class = "identifier" > ERM< / span > < span class = "plain" > )< / span >
< span class = "plain" > }< / span >
< span class = "reserved" > void< / span > < span class = "plain" > < / span > < span class = "functiontext" > Errors::with_text< / span > < span class = "plain" > (< / span > < span class = "reserved" > char< / span > < span class = "plain" > *< / span > < span class = "identifier" > message< / span > < span class = "plain" > , < / span > < span class = "reserved" > text_stream< / span > < span class = "plain" > *< / span > < span class = "identifier" > T< / span > < span class = "plain" > ) {< / span >
< span class = "identifier" > TEMPORARY_TEXT< / span > < span class = "plain" > (< / span > < span class = "identifier" > ERM< / span > < span class = "plain" > )< / span >
< span class = "identifier" > WRITE_TO< / span > < span class = "plain" > (< / span > < span class = "identifier" > ERM< / span > < span class = "plain" > , < / span > < span class = "string" > "%s: "< / span > < span class = "plain" > , < / span > < span class = "identifier" > INTOOL_NAME< / span > < span class = "plain" > );< / span >
< span class = "identifier" > WRITE_TO< / span > < span class = "plain" > (< / span > < span class = "identifier" > ERM< / span > < span class = "plain" > , < / span > < span class = "identifier" > message< / span > < span class = "plain" > , < / span > < span class = "identifier" > T< / span > < span class = "plain" > );< / span >
< span class = "identifier" > WRITE_TO< / span > < span class = "plain" > (< / span > < span class = "identifier" > ERM< / span > < span class = "plain" > , < / span > < span class = "string" > "\< / span > < span class = "plain" > n< / span > < span class = "string" > "< / span > < span class = "plain" > );< / span >
< span class = "functiontext" > Errors::issue< / span > < span class = "plain" > (< / span > < span class = "identifier" > ERM< / span > < span class = "plain" > , < / span > < span class = "constant" > FALSE< / span > < span class = "plain" > );< / span >
< span class = "identifier" > DISCARD_TEXT< / span > < span class = "plain" > (< / span > < span class = "identifier" > ERM< / span > < span class = "plain" > )< / span >
< span class = "plain" > }< / span >
< / pre >
< p class = "inwebparagraph" > < / p >
< p class = "endnote" > The function Errors::with_file is used in 4/tf (< a href = "4-tf.html#SP5_1" > § 5.1< / a > , < a href = "4-tf.html#SP5_2" > § 5.2< / a > , < a href = "4-tf.html#SP5_3_2" > § 5.3.2< / a > ).< / p >
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< p class = "endnote" > The function Errors::with_text is used in 8/bf (< a href = "8-bf.html#SP9" > § 9< / a > ).< / p >
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< hr class = "tocbar" >
< ul class = "toc" > < li > < i > (This section begins Chapter 3: The Operating System.)< / i > < / li > < li > < a href = "3-cla.html" > Continue with 'Command Line Arguments'< / a > < / li > < / ul > < hr class = "tocbar" >
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<!-- End of weave -->
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< / main >
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< / body >
< / html >