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
 | 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
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