CTERMID(3) BSD Library Functions Manual CTERMID(3)NAME
ctermid — generate terminal pathname
Standard C Library (libc, -lc)
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. Oth‐
erwise, 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’.
Upon successful completion, a non-NULL pointer is returned. Otherwise, a
NULL pointer is returned and the global variable errno is set to indicate
The current implementation detects no error conditions.
The ctermid() function conforms to IEEE Std 1003.1-1988 (“POSIX.1”).
By default the ctermid() function writes all information to an internal
static object. Subsequent calls to ctermid() will modify the same
BSD June 4, 1993 BSD