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Diffstat (limited to 'upstream/fedora-40/man3/ttyname.3')
-rw-r--r-- | upstream/fedora-40/man3/ttyname.3 | 111 |
1 files changed, 111 insertions, 0 deletions
diff --git a/upstream/fedora-40/man3/ttyname.3 b/upstream/fedora-40/man3/ttyname.3 new file mode 100644 index 00000000..9007204d --- /dev/null +++ b/upstream/fedora-40/man3/ttyname.3 @@ -0,0 +1,111 @@ +'\" t +.\" Copyright (c) 1995 Jim Van Zandt <jrv@vanzandt.mv.com> +.\" +.\" SPDX-License-Identifier: GPL-2.0-or-later +.\" +.\" Modified 2001-12-13, Martin Schulze <joey@infodrom.org> +.\" Added ttyname_r, aeb, 2002-07-20 +.\" +.TH ttyname 3 2023-10-31 "Linux man-pages 6.06" +.SH NAME +ttyname, ttyname_r \- return name of a terminal +.SH LIBRARY +Standard C library +.RI ( libc ", " \-lc ) +.SH SYNOPSIS +.nf +.B #include <unistd.h> +.P +.BI "char *ttyname(int " fd ); +.BI "int ttyname_r(int " fd ", char " buf [. buflen "], size_t " buflen ); +.fi +.SH DESCRIPTION +The function +.BR ttyname () +returns a pointer to the null-terminated pathname of the terminal device +that is open on the file descriptor \fIfd\fP, or NULL on error +(for example, if \fIfd\fP is not connected to a terminal). +The return value may point to static data, possibly overwritten by the +next call. +The function +.BR ttyname_r () +stores this pathname in the buffer +.I buf +of length +.IR buflen . +.SH RETURN VALUE +The function +.BR ttyname () +returns a pointer to a pathname on success. +On error, NULL is returned, and +.I errno +is set to indicate the error. +The function +.BR ttyname_r () +returns 0 on success, and an error number upon error. +.SH ERRORS +.TP +.B EBADF +Bad file descriptor. +.TP +.\" glibc commit 15e9a4f378c8607c2ae1aa465436af4321db0e23 +.B ENODEV +.I fd +refers to a slave pseudoterminal device +but the corresponding pathname could not be found (see NOTES). +.TP +.B ENOTTY +.I fd +does not refer to a terminal device. +.TP +.B ERANGE +.RB ( ttyname_r ()) +.I buflen +was too small to allow storing the pathname. +.SH ATTRIBUTES +For an explanation of the terms used in this section, see +.BR attributes (7). +.TS +allbox; +lbx lb lb +l l l. +Interface Attribute Value +T{ +.na +.nh +.BR ttyname () +T} Thread safety MT-Unsafe race:ttyname +T{ +.na +.nh +.BR ttyname_r () +T} Thread safety MT-Safe +.TE +.SH STANDARDS +POSIX.1-2008. +.SH HISTORY +POSIX.1-2001, 4.2BSD. +.SH NOTES +A process that keeps a file descriptor that refers to a +.BR pts (4) +device open when switching to another mount namespace that uses a different +.I /dev/ptmx +instance may still accidentally find that a device path of the same name +for that file descriptor exists. +However, this device path refers to a different device and thus +can't be used to access the device that the file descriptor refers to. +Calling +.BR ttyname () +or +.BR ttyname_r () +on the file descriptor in the new mount namespace will cause these +functions to return NULL and set +.I errno +to +.BR ENODEV . +.SH SEE ALSO +.BR tty (1), +.BR fstat (2), +.BR ctermid (3), +.BR isatty (3), +.BR pts (4) |