getpt(3) — Linux manual page

getpt(3)                Library Functions Manual                getpt(3)

NAME

       getpt - open a new pseudoterminal master

LIBRARY

       Standard C library (libc, -lc)

SYNOPSIS

       #define _GNU_SOURCE             /* See feature_test_macros(7) */
       #include <stdlib.h>

       int getpt(void);

DESCRIPTION

       getpt() opens a new pseudoterminal device and returns a file
       descriptor that refers to that device.  It is equivalent to
       opening the pseudoterminal multiplexor device

           open("/dev/ptmx", O_RDWR);

       on Linux systems, though the pseudoterminal multiplexor device is
       located elsewhere on some systems that use the GNU C library.

RETURN VALUE

       getpt() returns an open file descriptor upon successful
       completion.  Otherwise, it returns -1 and sets errno to indicate
       the error.

ERRORS

       getpt() can fail with various errors described in open(2).

ATTRIBUTES

       For an explanation of the terms used in this section, see
       attributes(7).
       ┌─────────────────────────────────────┬───────────────┬─────────┐
       │ Interface                           Attribute     Value   │
       ├─────────────────────────────────────┼───────────────┼─────────┤
       │ getpt()                             │ Thread safety │ MT-Safe │
       └─────────────────────────────────────┴───────────────┴─────────┘

VERSIONS

       Use posix_openpt(3) instead.

STANDARDS

       GNU.

HISTORY

       glibc 2.1.

SEE ALSO

       grantpt(3), posix_openpt(3), ptsname(3), unlockpt(3), ptmx(4),
       pty(7)

COLOPHON

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Linux man-pages 6.9.1          2024-05-02                       getpt(3)

Pages that refer to this page: posix_openpt(3), pts(4)