getusershell(3) - Linux manual page (original) (raw)
getusershell(3) Library Functions Manual getusershell(3)
NAME top
getusershell, setusershell, endusershell - get permitted user
shells
LIBRARY top
Standard C library (_libc_, _-lc_)
SYNOPSIS top
**#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 top
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 top
The **getusershell**() function returns NULL on end-of-file.
FILES top
_/etc/shells_
ATTRIBUTES top
For an explanation of the terms used in this section, see
[attributes(7)](../man7/attributes.7.html).
┌────────────────────────────────────┬───────────────┬───────────┐
│ **Interface** │ **Attribute** │ **Value** │
├────────────────────────────────────┼───────────────┼───────────┤
│ **getusershell**(), **setusershell**(), │ Thread safety │ MT-Unsafe │
│ **endusershell**() │ │ │
└────────────────────────────────────┴───────────────┴───────────┘
STANDARDS top
None.
HISTORY top
4.3BSD.
SEE ALSO top
[shells(5)](../man5/shells.5.html)
COLOPHON top
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Linux man-pages 6.10 2024-07-23 getusershell(3)
Pages that refer to this page:shells(5)