TCGETSID(3) | Library Functions Manual | TCGETSID(3)

# NAME

`tcgetsid` — get session ID associated with a controlling terminal

# SYNOPSIS

`#include <termios.h>`

pid_t
`tcgetsid`(int fd);

# DESCRIPTION

The `tcgetsid`() function returns the value of the session ID associated with the specified controlling terminal device. The session ID is defined as the process group ID of the session leader.

# ERRORS

If an error occurs, `tcgetsid`() returns -1 and the global variable errno is set to indicate the error, as follows:

[`EBADF`]
  The fd argument is not a valid file descriptor.
[`ENOTTY`]
  The calling process does not have a controlling terminal or the underlying terminal device represented by fd is not the controlling terminal.

# SEE ALSO

getsid(2), setsid(2), tcgetpgrp(3)

# STANDARDS

The `tcgetsid`() function is compliant with the IEEE Std 1003.1-2008 (“POSIX.1”) specification.

# HISTORY

The `tcgetsid`() function has been available since OpenBSD 5.5.

January 12, 2023 | Debian