getpt(3) — Linux manual page

getpt(3)                Library Functions Manual                getpt(3)

NAME         top

       getpt - open a new pseudoterminal master

LIBRARY         top

       Standard C library (libc, -lc)

SYNOPSIS         top

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

       int getpt(void);

DESCRIPTION         top

       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         top

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

ERRORS         top

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

ATTRIBUTES         top

       For an explanation of the terms used in this section, see
       attributes(7).

       ┌──────────────────────────────────────┬───────────────┬─────────┐
       │Interface                             │ Attribute     │ Value   │
       ├──────────────────────────────────────┼───────────────┼─────────┤
       │getpt()                               │ Thread safety │ MT-Safe │
       └──────────────────────────────────────┴───────────────┴─────────┘

VERSIONS         top

       Use posix_openpt(3) instead.

STANDARDS         top

       GNU.

HISTORY         top

       glibc 2.1.

SEE ALSO         top

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

Linux man-pages 6.04           2023-03-30                       getpt(3)

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

Copyright and license for this manual page

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