POSIX_OPENPTSection: Linux Programmer's Manual (3)
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NAMEposix_openpt - open a pseudoterminal device
Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
DESCRIPTIONThe posix_openpt() function opens an unused pseudoterminal master device, returning a file descriptor that can be used to refer to that device.
The flags argument is a bit mask that ORs together zero or more of the following flags:
- Open the device for both reading and writing. It is usual to specify this flag.
- Do not make this device the controlling terminal for the process.
RETURN VALUEOn success, posix_openpt() returns a file descriptor (a nonnegative integer) which is the lowest numbered unused file descriptor. On failure, -1 is returned, and errno is set to indicate the error.
VERSIONSGlibc support for posix_openpt() has been provided since version 2.2.1.
ATTRIBUTESFor an explanation of the terms used in this section, see attributes(7).
CONFORMING TOPOSIX.1-2001, POSIX.1-2008.
posix_openpt() is part of the UNIX 98 pseudoterminal support (see pts(4)).
NOTESSome older UNIX implementations that support System V (aka UNIX 98) pseudoterminals don't have this function, but it can be easily implemented by opening the pseudoterminal multiplexor device:
return open("/dev/ptmx", flags); }
Calling posix_openpt() creates a pathname for the corresponding pseudoterminal slave device. The pathname of the slave device can be obtained using ptsname(3). The slave device pathname exists only as long as the master device is open.
SEE ALSOopen(2), getpt(3), grantpt(3), ptsname(3), unlockpt(3), pts(4), pty(7)
COLOPHONThis page is part of release 5.10 of the Linux man-pages project. A description of the project, information about reporting bugs, and the latest version of this page, can be found at https://www.kernel.org/doc/man-pages/.
- RETURN VALUE
- CONFORMING TO
- SEE ALSO
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