NAME
ctermid, ctermid_r – generate terminal pathname
LIBRARY
Standard C Library (libc, -lc)
SYNOPSIS
#include <stdio.h>
char *
ctermid(char *buf);
char *
ctermid_r(char *buf);
DESCRIPTION
The ctermid() function generates a string, that, when used as a pathname, refers to the current controlling terminal of the calling process.
If buf is the NULL pointer, a pointer to a static area is returned. Otherwise, the pathname is copied into the memory referenced by buf. The argument buf is assumed to be at least L_ctermid (as defined in the include file ⟨stdio.h⟩) bytes long.
The ctermid_r() function provides the same functionality as ctermid() except that if buf is a NULL pointer, NULL is returned.
The current implementation simply returns ‘/dev/tty’.
RETURN VALUES
The ctermid() function returns buf if it is non-NULL, otherwise it returns the address of a static buffer. The ctermid_r() function always returns buf, even if it is the NULL pointer.
ERRORS
The current implementation detects no error conditions.
SEE ALSO
STANDARDS
The ctermid() function conforms to IEEE Std 1003.1-1988 (“POSIX.1”).
BUGS
By default the ctermid() function writes all information to an internal static object. Subsequent calls to ctermid() will modify the same object.