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30.Dd $Mdocdate: January 21 2014 $
31.Dt CTERMID 3
32.Os
33.Sh NAME
34.Nm ctermid
35.Nd generate terminal pathname
36.Sh SYNOPSIS
37.In stdio.h
38.Ft char *
39.Fn ctermid "char *buf"
40.Sh DESCRIPTION
41The
42.Fn ctermid
43function generates a string that, when used as a pathname, refers to
44the current controlling terminal of the calling process.
45.Pp
46If
47.Ar buf
48is a null pointer, a pointer to a static area is returned.
49Otherwise, the pathname is copied into the memory referenced by
50.Ar buf .
51The argument
52.Ar buf
53is assumed to point to an array at least
54.Dv L_ctermid
55(as defined in the include
56file
57.In stdio.h )
58bytes long.
59.Pp
60The current implementation simply generates
61.Qq /dev/tty .
62.Sh RETURN VALUES
63The
64.Fn ctermid
65function returns a non-null pointer, which is equal to the
66.Ar buf
67argument if it is not
68.Dv NULL .
69.Sh ERRORS
70The current implementation detects no error conditions.
71.Sh SEE ALSO
72.Xr ttyname 3
73.Sh STANDARDS
74The
75.Fn ctermid
76function conforms to
77.St -p1003.1-88 .
78