NAME
tcgetsid() — get terminal session ID
SYNOPSIS
#include <termios.h>
pid_t tcgetsid (int fildes);
DESCRIPTION
The
tcgetsid()
function returns the value of the session ID of the
foreground process associated with the terminal referenced by
fildes.
tcgetsid()
is allowed from a process that is a member of a
background process group (see
termio(7)).
RETURN VALUE
Upon successful completion,
tcgetsid()
returns the value of the
session ID of the foreground process associated with the
terminal referenced by
fildes.
Otherwise,
tcgetsid()
returns a value of
-1
and sets
errno
to indicate the error.
ERRORS
If the
tcgetsid()
function fails, it sets
errno
(see
errno(2))
to one of the following values:
- [EACCES]
The file associated with
fildes
is the controlling
terminal of the calling process;
however, there is
no foreground process group defined for the
controlling terminal.
- [EBADF]
fildes
is not a valid file descriptor.
- [ENOTTY]
The file associated with
fildes
is not the
controlling terminal or the calling process does
not have a controlling terminal.
APPLICATION USAGE
tcgetsid()
is thread-safe and async-cancel-safe.
