Section (3) tcgetsid
tcgetsid — get session ID
#define _XOPEN_SOURCE 500 /* See feature_test_macros(7) */ #include <termios.h>
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
fd refers to
the controlling terminal of our session, the function
tcgetsid() will return the
session ID of this session. Otherwise, −1 is returned,
errno is set
fdis not a valid file descriptor.
The calling process does not have a controlling terminal, or it has one but it is not described by
For an explanation of the terms used in this section, see attributes(7).
This function is implemented via the
TIOCGSID ioctl(2), present since
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Copyright (C) 2002 Andries Brouwer <aebcwi.nl>
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