getlogin_r
==========

POSIX specification:
 http://www.opengroup.org/onlinepubs/9699919799/functions/getlogin_r.html

Gnulib module: getlogin_r

Portability problems fixed by Gnulib:

  * This function is missing on some platforms: NetBSD 3.0, mingw.

  * This function is not declared unless _REENTRANT is defined, on some platforms: HP-UX 11.

  * This function has an incompatible declaration on some platforms: Solaris 11 2010-11 (when _POSIX_PTHREAD_SEMANTICS is not defined).

  * This function returns a truncated result, instead of failing with error code ERANGE, when the buffer is not large enough, on some platforms: OSF/1 5.1.

Portability problems not fixed by Gnulib:

  * This function fails even when standard input is a tty on some platforms: HP-UX 11.11.

  * This function fails with error code EINVAL instead of ERANGE when the second argument is zero on some platforms: HP-UX 11.31.