grantpt - Permits access to the slave pseudoterminal device
Standard C Library (libc.so, libc.a)
Interfaces documented on this reference page conform to industry standards as follows:
Refer to the standards(5) reference page for more information about industry standards and associated tags.
Specifies a file descriptor that is returned from a successful open of a master pseudoterminal device.
The grantpt() function modifies the ownership and mode of the slave pseudoterminal device associated with its master pseudoterminal counterpart.
The modifications of mode and ownership are performed as follows: The group ID is set to a reserved group. The slave user ID is set to the real UID of the calling process. The permissions of the slave device are set so that the owner is allowed read and write access and the group is allowed write access.
Upon successful completion, the grantpt() function returns a value of 0 (zero). Otherwise, it returns a value of -1 and sets errno to indicate the error.
The grantpt() function sets errno to the specified values for the following conditions:
The corresponding slave device cannot be accessed. The file descriptor specified by the fildes parameter is not a valid open file descriptor. The file descriptor specified by the fildes parameter is not associated with a master device.
The grantpt() function may also fail if the application has installed a signal handler to catch SIGCHLD (death of a child) signals.
Applications calling grantpt() may get a SIGCHLD signal from processes that they did not explicitly create.
Functions: open(2), ptsname(3), setuid(2), unlockpt(3)
Standards: standards(5) delim off