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.Dd December 20, 2003
.Dt tcgetsid 3
.Os
.Sh NAME
.Nm tcgetsid
.Nd get the process group ID for the session leader for the controlling terminal
.Sh SYNOPSIS
.In termios.h
.Ft pid_t
.Fo tcgetsid
.Fa "int fildes"
.Fc
.Sh DESCRIPTION
The
.Fn tcgetsid
function obtains the process group ID of the session for which the terminal
specified by
.Fa fildes
is the controlling terminal.
.Sh RETURN VALUES
Upon successful completion,
.Fn tcgetsid
returns the process group ID associated with the terminal.
Otherwise, a value of
.Po Vt pid_t Pc Ns -1
is returned and
.Va errno
is set to indicate the error.
.Sh ERRORS
The
.Fn tcgetsid
function will fail if:
.Bl -tag -width Er
.It Bq Er EACCES
The
.Vt fildes
argument is not associated with a controlling terminal.
.It Bq Er EBADF
The
.Vt fildes
argument is not a valid file descriptor.
.It Bq Er ENOTTY
The file associated with
.Vt fildes
is not a terminal.
.El
.Sh SEE ALSO
.Xr getsid 2 ,
.Xr setpgid 2 ,
.Xr setsid 2 ,
.Xr tcgetpgrp 3 ,
.Xr termios 4
.Sh STANDARDS
The
.Fn tcgetsid
function conforms to
.St -p1003.1-2001 .