tcgetsid - get session ID
#define _XOPEN_SOURCE 500
/* See feature_test_macros(7) */
pid_t tcgetsid(int fd);
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.
refers to the controlling terminal of our session, the function
() will return the session ID of this session. Otherwise, -1 is
returned, and errno
is set appropriately.
- fd is not a valid file descriptor.
- The calling process does not have a controlling terminal, or it has one
but it is not described by fd.
() is provided in glibc since version 2.1.
For an explanation of the terms used in this section, see attributes
This function is implemented via the TIOCGSID ioctl
since Linux 2.1.71.