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NAME

       grantpt - grant access to the slave pseudo-terminal

SYNOPSIS

       #define _XOPEN_SOURCE
       #include <stdlib.h>

       int grantpt(int fd);

DESCRIPTION

       The  grantpt() function changes the mode and owner of the slave pseudo-
       terminal device (pty) corresponding to the master pty  referred  to  by
       fd.   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).  The
       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 signals.

RETURN VALUE

       When successful, grantpt() returns 0.  Otherwise,  it  returns  -1  and
       sets errno appropriately.

ERRORS

       EACCES The corresponding slave pty could not be accessed.

       EBADF  The fd argument is not a valid open file descriptor.

       EINVAL The fd argument is valid but not associated with a master pty.

VERSIONS

       grantpt() is provided in glibc since version 2.1.

CONFORMING TO

       POSIX.1-2001.

NOTES

       This  is  part  of  the  Unix98  pty support, see pts(4).  Many systems
       implement  this  function  via  a  set-user-ID  helper  binary   called
       "pt_chown".  With Linux devpts no such helper binary is required.

SEE ALSO

       open(2),     posix_openpt(3),    ptsname(3),    unlockpt(3),    pts(4),
       feature_test_macros(7), pty(7)

COLOPHON

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