Implementation definition
Appendix G of the ISO C standard (ISO/IEC 9899:1990 (E)) collates
information about portability issues. Sub-clause G3 lists the behavior
that each implementation must document.
Note
This appendix does not duplicate information that is part
of Compiler-specific Features. This
appendix provides references where applicable.
The following topics correspond to the relevant sections of
sub-clause G3. They describe aspects of the ARM C compiler and C
library, not defined by the ISO C standard, that are implementation-defined:
Note
The support for the wctype.h and wchar.h headers
excludes wide file operations.
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