Include fcntl.h so AT_FDCWD does not get redefined.

[collinfunk]

The bsd-misc.h header will define AT_FDCWD and implement the *at functions to set errno = ENOSYS, which is reasonable on systems lacking them.

However, before defining AT_FDCWD, <fcntl.h> should be included where POSIX requires it to be defined [1].

The following GCC warning should make things clear:

In file included from port-net.c:27:
/usr/include/fcntl.h:149:10: warning: "AT_FDCWD" redefined
  149 | # define AT_FDCWD               -100    /* Special value used to indicate
      |          ^~~~~~~~
In file included from ../openbsd-compat/openbsd-compat.h:218:
../openbsd-compat/bsd-misc.h:69:10: note: this is the location of the previous definition
   69 | # define AT_FDCWD (-2)
      |          ^~~~~~~~

configure.ac already has AC_CHECK_HEADERS([fcntl.h]), so just adding the include fixes it.

[1] https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/fcntl.h.html

[daztucker]

Applied, thanks.