| @node unsetenv |
| @section @code{unsetenv} |
| @findex unsetenv |
| |
| POSIX specification:@* @url{https://pubs.opengroup.org/onlinepubs/9699919799/functions/unsetenv.html} |
| |
| Gnulib module: unsetenv |
| |
| Portability problems fixed by Gnulib: |
| @itemize |
| @item |
| This function is missing on some platforms: |
| AIX 5.1, HP-UX 11.23, IRIX 6.5, Solaris 9, mingw, MSVC 14. |
| @item |
| This function has the return type @samp{void} instead of @samp{int} on some |
| platforms: |
| FreeBSD 6.0, NetBSD 1.6, OpenBSD 3.8. |
| @item |
| On some platforms, this function does not fail with @samp{EINVAL} when |
| passed an empty string or a string containing @samp{=}: |
| FreeBSD 6.0, NetBSD 1.6, OpenBSD 4.7. |
| @item |
| This function removes only the first value association for the given |
| environment variable, not all of them, on some platforms: |
| Solaris 11.4, Haiku. |
| @end itemize |
| |
| Portability problems not fixed by Gnulib: |
| @itemize |
| @item |
| Older versions of POSIX required that @code{unsetenv(NULL)} gracefully |
| fail with @code{EINVAL}, but not all implementations guarantee this, |
| and the requirement was removed. |
| @end itemize |
