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():

    Since glibc 2.21:


        _DEFAULT_SOURCE


    In glibc 2.19 and 2.20:


        _DEFAULT_SOURCE || (_XOPEN_SOURCE && _XOPEN_SOURCE < 500)


    Up to and including glibc 2.19:


        _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

For an explanation of the terms used in this section, see attributes(7).

CONFORMING TO

4.3BSD.

SEE ALSO

shells(5)

COLOPHON

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