Add description for _LARGEFILE_SOURCE, _LARGEFILE64_SOURCE, _FILE_OFFSET_BITS and __USE_LARGEFILE, __USE_LARGEFILE64 and __USE_FILE_OFFSET64 macros. Signed-off-by: Max Filippov <jcmvbkbc(a)gmail.com> --- Changes v1->v2: - fix subject line docs/defines.txt | 23 ++++++++++++++++++++--- 1 file changed, 20 insertions(+), 3 deletions(-) diff --git a/docs/defines.txt b/docs/defines.txt index b23fac9c0036..6af44bdd809f 100644 --- a/docs/defines.txt +++ b/docs/defines.txt @@ -10,11 +10,28 @@ __USE_GNU, __USE_BSD, __USE_XOPEN[2K], __USE_SVID, __USE_POSIX... If defined, user program which included us requests compat additions from relevant standard or Unix flavor. See features.h for full list. -__USE_FILE_OFFSET64 +_LARGEFILE_SOURCE + If defined, headers will provide functions fseeko and ftello. +_LARGEFILE64_SOURCE + If defined, headers will in addition to data types, constants and + functions named xxx (e.g. off_t, struct stat, F_SETLK, ftruncate()) + supply data types, constants and functions named xxx64 (e.g. off64_t, + struct stat64, F_SETLK64, ftruncate64()) known as an interface for + 64-bit file offsets. __USE_LARGEFILE[64] -_LARGEFILE[64]_SOURCE + Defined to 1 and used internally when built with _LARGEFILE[64]_SOURCE. + Undefined otherwise. + _FILE_OFFSET_BITS - ??? + Select default filesystem interface. When defined as 64 the data types, + constants and functions mentioned in _LARGEFILE64_SOURCE as xxx are + aliased to the corresponding xxx64 data types, constants and functions. + _FILE_OFFSET_BITS=64 enables both __USE_LARGEFILE and __USE_LARGEFILE64. + This flag does not affect the way libc itself is built, it only affects + what declarations are provided to library user. +__USE_FILE_OFFSET64 + Defined to 1 and used internally when built with _FILE_OFFSET_BITS=64. + Undefined otherwise. __THROW Function annotation "I do not throw anything". -- 2.11.0