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Diffstat (limited to 'manual/creature.texi')
| -rw-r--r-- | manual/creature.texi | 33 |
1 files changed, 26 insertions, 7 deletions
diff --git a/manual/creature.texi b/manual/creature.texi index 03f79ede96..1efd1f5a7d 100644 --- a/manual/creature.texi +++ b/manual/creature.texi @@ -25,17 +25,36 @@ self-contained way. If you define this macro, then the functionality from the POSIX.1 standard (IEEE Standard 1003.1) is available, as well as all of the @w{ISO C} facilities. + +The state of @code{_POSIX_SOURCE} is irrelevant if you define the +macro @code{_POSIX_C_SOURCE} to a positive integer. @end defvr @comment (none) @comment POSIX.2 -@defvr Macro _POSIX_C_SOURCE -If you define this macro with a value of @code{1}, then the -functionality from the POSIX.1 standard (IEEE Standard 1003.1) is made -available. If you define this macro with a value of @code{2}, then both -the functionality from the POSIX.1 standard and the functionality from -the POSIX.2 standard (IEEE Standard 1003.2) are made available. This is -in addition to the @w{ISO C} facilities. +Define this macro to a positive integer to control which POSIX +functionality is made available. The greater the value of this macro, +the more functionality is made available. + +If you define this macro to a value greater than or equal to @code{1}, +then the functionality from the 1990 edition of the POSIX.1 standard +(IEEE Standard 1003.1-1990) is made available. + +If you define this macro to a value greater than or equal to @code{2}, +then the functionality from the 1992 edition of the POSIX.2 standard +(IEEE Standard 1003.2-1992) is made available. + +If you define this macro to a value greater than or equal to @code{199309L}, +then the functionality from the 1993 edition of the POSIX.1b standard +(IEEE Standard 1003.1b-1993) is made available. + +Greater values for @code{_POSIX_C_SOURCE} will enable future extensions. +The POSIX standards process will define these values as necessary, and +the GNU C Library should support them some time after they become standardized. +The 1996 edition of POSIX.1 (ISO/IEC 9945-1: 1996) states that +if you define @code{_POSIX_C_SOURCE} to a value greater than +or equal to @code{199506L}, then the functionality from the 1996 +edition is made available. The Single Unix Specification specify that setting this macro to the value @code{199506L} selects all the values specified by the POSIX |