tcgetsid - get session ID
#define _XOPEN_SOURCE 500 /* See feature_test_macros(7) */
#include <termios.h>
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.
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.
getsid(2)