1
0
mirror of https://git.savannah.gnu.org/git/gnulib.git synced 2025-08-16 01:22:18 +03:00
Files
gnulib/doc/posix-functions/gettimeofday.texi
Bruno Haible 055746f501 gettimeofday: Increase precision on mingw.
* m4/gettimeofday.m4 (gl_FUNC_GETTIMEOFDAY): Require AC_CANONICAL_HOST.
Set REPLACE_GETTIMEOFDAY to 1 on mingw.
* lib/gettimeofday.c (gettimeofday): On native Windows, use the
GetSystemTimePreciseAsFileTime based implementation always.
* doc/posix-functions/gettimeofday.texi: Mention precision problem on
mingw.
2017-05-11 21:39:06 +02:00

41 lines
1.2 KiB
Plaintext

@node gettimeofday
@section @code{gettimeofday}
@findex gettimeofday
POSIX specification:@* @url{http://www.opengroup.org/onlinepubs/9699919799/functions/gettimeofday.html}
Gnulib module: gettimeofday
Portability problems fixed by Gnulib:
@itemize
@item
This function is missing on some platforms:
MSVC 9.
@item
This function is declared with a nonstandard function prototype (only one
argument, or ``...'' after the first argument) on some platforms.
@item
On some platforms, the second argument has type @code{struct
timezone*} rather than @code{void *}, making it an error to redeclare
the function with the POSIX signature:
glibc.
However, rather than penalize these systems with a replacement
function, gnulib defines @code{GETTIMEOFDAY_TIMEZONE} to the
appropriate type for use in avoiding a compiler warning if assigning
@code{gettimeofday} to a function pointer.
@item
On some platforms, @code{gettimeofday} clobbers the buffer in which
@code{localtime} returns its result:
Mac OS X 10.0.
@item
This function has only a precision of 15.6 milliseconds on some platforms:
mingw.
@end itemize
Portability problems not fixed by Gnulib:
@itemize
@item
Behavior is non-portable if the second argument to @code{gettimeofday}
is not @code{NULL}.
@end itemize