Manpages - getusershell.3

getusershell, setusershell, endusershell - get permitted user shells

  #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)

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.

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

/etc/shells

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

4.3BSD.

*shells*(5)

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