Gnulib module: fchmodat
Portability problems fixed by Gnulib:
Portability problems not fixed by Gnulib:
fchmodat(...,AT_SYMLINK_NOFOLLOW)may fail with
EOPNOTSUPPwhen called on a symlink, but some platforms, as well as the gnulib replacement, fail for any use of AT_SYMLINK_NOFOLLOW even if the target was not a symlink: glibc, Cygwin.