grantpt - grant access to the slave pseudoterminal
#define _XOPEN_SOURCE /* See feature_test_macros(7) */
int grantpt(int fd);
() function changes the mode and owner of the slave
pseudoterminal device corresponding to the master pseudoterminal referred to
. The user ID of the slave is set to the real UID of the calling
process. The group ID is set to an unspecified value (e.g., tty
mode of the slave is set to 0620 (crw--w----).
The behavior of grantpt
() is unspecified if a signal handler is installed
to catch SIGCHLD
When successful, grantpt
() returns 0. Otherwise, it returns -1 and sets
- The corresponding slave pseudoterminal could not be accessed.
- The fd argument is not a valid open file descriptor.
- The fd argument is valid but not associated with a master
() is provided in glibc since version 2.1.
This is part of the UNIX 98 pseudoterminal support, see pts(4)
systems implement this function via a set-user-ID helper binary called
"pt_chown". With Linux devpts no such helper binary is required.
This page is part of release 3.74 of the Linux man-pages
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