GETUSERSHELL(3)                     Linux Programmer's Manual                     GETUSERSHELL(3)



NAME
       getusershell, setusershell, endusershell - get permitted user shells

SYNOPSIS
       #include <unistd.h>

       char *getusershell(void);

       void setusershell(void);

       void endusershell(void);

   Feature Test Macro Requirements for glibc (see feature_test_macros(7)):

       getusershell(), setusershell(), endusershell():
           _BSD_SOURCE || (_XOPEN_SOURCE && _XOPEN_SOURCE < 500)

DESCRIPTION
       The  getusershell()  function returns the next line from the file /etc/shells, opening the
       file if necessary.  The line should contain the  pathname  of  a  valid  user  shell.   If
       /etc/shells  does  not  exist  or  is unreadable, getusershell() behaves as if /bin/sh and
       /bin/csh were listed in the file.

       The setusershell() function rewinds /etc/shells.

       The endusershell() function closes /etc/shells.

RETURN VALUE
       The getusershell() function returns NULL on end-of-file.

FILES
       /etc/shells

ATTRIBUTES
   Multithreading (see pthreads(7))
       The getusershell(), setusershell() and endusershell() functions are not thread-safe.

CONFORMING TO
       4.3BSD.

SEE ALSO
       shells(5)

COLOPHON
       This page is part of release 3.74 of the Linux man-pages project.  A  description  of  the
       project,  information  about  reporting  bugs, and the latest version of this page, can be
       found at http://www.kernel.org/doc/man-pages/.



GNU                                         2013-06-21                            GETUSERSHELL(3)