The following macros check for certain operating systems that need special treatment for some programs, due to exceptional oddities in their header files or libraries. These macros are warts; they will be replaced by a more systematic approach, based on the functions they make available or the environments they provide.
For interactive Systems Corporation Unix, add -lcposix to output variable
LIBSif necessary for Posix facilities. Call this after
AC_PROG_CCand before any other macros that use Posix interfaces. interactive Unix is no longer sold, and Sun says that they will drop support for it on 2006-07-23, so this macro is becoming obsolescent.
If possible, enable extensions to Posix on hosts that normally disable the extensions, typically due to standards-conformance namespace issues. This may involve defining
_POSIX_PTHREAD_SEMANTICS, which are macros used by Solaris. This macro also has the combined effects of