diff options
Diffstat (limited to 'share/man/man9/posix4.9')
-rw-r--r-- | share/man/man9/posix4.9 | 15 |
1 files changed, 11 insertions, 4 deletions
diff --git a/share/man/man9/posix4.9 b/share/man/man9/posix4.9 index 0cdec81..eeb191b 100644 --- a/share/man/man9/posix4.9 +++ b/share/man/man9/posix4.9 @@ -85,7 +85,9 @@ is a test macro that sorts out when extensions should be visible. It is defined in <sys/_posix.h>. .Pp In normal C program development -only _POSIX_VERSION is set, permitting BSD extensions to +only _POSIX_VERSION is set, permitting +.Bx +extensions to appear to the programs. However, when adding new functionality mandated by POSIX.1B, it is important to satisfy the requirements added by the @@ -99,16 +101,21 @@ is present to conditionalize POSIX.1B extensions that were historically in the system. These are visible when _POSIX_SOURCE and _POSIX_C_SOURCE are not set at all or when _POSIX_C_SOURCE enables POSIX.1B features. The intent of this feature test is to permit hiding the new extensions -while still letting BSD extensions show up to avoid breaking existing +while still letting +.Bx +extensions show up to avoid breaking existing programs without trying to use the "big hammer" of _POSIX_C_SOURCE. .Pp Some recent additions to header files are new enough that they should be changed to be dependent on _P1003_1B_VISIBLE instead of _HISTORICALLY. .Pp -Traditional BSD headers (e.g., mmap.h) now specified +Traditional +.Bx +headers (e.g., mmap.h) now specified in POSIX.1B can include <sys/_posix.h> and conditionalize -BSD extensions on _P1003_1B_VISIBLE_HISTORICALLY. +.Bx +extensions on _P1003_1B_VISIBLE_HISTORICALLY. .Sh NON STANDARD TEST MACROS .Bd -literal -offset 0i _P1003_1B_INCLUDE_MAYBES |