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tcgetsid(3)


NAME

   tcgetsid - get session ID

SYNOPSIS

   #define _XOPEN_SOURCE 500        /* See feature_test_macros(7) */
   #include <termios.h>

   pid_t tcgetsid(int fd);

DESCRIPTION

   The  function  tcgetsid() returns the session ID of the current session
   that has the terminal associated to fd as controlling  terminal.   This
   terminal must be the controlling terminal of the calling process.

RETURN VALUE

   When fd refers to the controlling terminal of our session, the function
   tcgetsid() will return the session ID of this session.   Otherwise,  -1
   is returned, and errno is set appropriately.

ERRORS

   EBADF  fd is not a valid file descriptor.

   ENOTTY The  calling process does not have a controlling terminal, or it
          has one but it is not described by fd.

VERSIONS

   tcgetsid() is provided in glibc since version 2.1.

ATTRIBUTES

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

   
   Interface   Attribute      Value   
   
   tcgetsid()  Thread safety  MT-Safe

CONFORMING TO

   POSIX.1-2001, POSIX.1-2008.

NOTES

   This  function  is implemented via the TIOCGSID ioctl(2), present since
   Linux 2.1.71.

SEE ALSO

   getsid(2)

COLOPHON

   This page is part of release 4.09 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
   https://www.kernel.org/doc/man-pages/.



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