tcgetsid(3) Library Functions Manual tcgetsid(3)
NAME
tcgetsid - get session ID
LIBRARY
Standard C library (libc, -lc)
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 to indicate the error.
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.
ATTRIBUTES
For an explanation of the terms used in this section, see attributes(7).
┌────────────────────────────────────────────┬───────────────┬─────────┐
│ Interface │ Attribute │ Value │
├────────────────────────────────────────────┼───────────────┼─────────┤
│ tcgetsid() │ Thread safety │ MT-Safe │
└────────────────────────────────────────────┴───────────────┴─────────┘
STANDARDS
POSIX.1-2008.
HISTORY
glibc 2.1. POSIX.1-2001.
This function is implemented via the TIOCGSID ioctl(2), present since
Linux 2.1.71.
SEE ALSO
getsid(2)
Linux man-pages 6.9.1 2024-05-02 tcgetsid(3)
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