diff options
| author | Max Filippov <jcmvbkbc@gmail.com> | 2019-05-10 12:51:25 -0700 |
|---|---|---|
| committer | Waldemar Brodkorb <wbx@openadk.org> | 2019-05-13 09:11:01 +0200 |
| commit | 30b85d43a7657eeac02462e8d84946358a5aa647 (patch) | |
| tree | 801bb9bc01ac6d26bbd35e84a829ab62b9b03d25 /docs/defines.txt | |
| parent | 89873385e4fa219d8dbdd708c9d92214916dc1e8 (diff) | |
docs/defines.txt: clarify LFS-related macros
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@gmail.com>
Diffstat (limited to 'docs/defines.txt')
| -rw-r--r-- | docs/defines.txt | 23 |
1 files changed, 20 insertions, 3 deletions
diff --git a/docs/defines.txt b/docs/defines.txt index b23fac9c0..6af44bdd8 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". |