grantpt(3)

1GRANTPT(3)                 Linux Programmer's Manual                GRANTPT(3)
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NAME

6       grantpt - grant access to the slave pseudoterminal
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SYNOPSIS

9       #define _XOPEN_SOURCE       /* See feature_test_macros(7) */
10       #include <stdlib.h>
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12       int grantpt(int fd);
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DESCRIPTION

15       The  grantpt()  function  changes the mode and owner of the slave pseu‐
16       doterminal device corresponding to the master  pseudoterminal  referred
17       to by fd.  The user ID of the slave is set to the real UID of the call‐
18       ing process.  The group ID is set to an unspecified value (e.g.,  tty).
19       The mode of the slave is set to 0620 (crw--w----).
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21       The  behavior  of  grantpt()  is  unspecified  if  a  signal handler is
22       installed to catch SIGCHLD signals.
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RETURN VALUE

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

29       EACCES The corresponding slave pseudoterminal could not be accessed.
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31       EBADF  The fd argument is not a valid open file descriptor.
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33       EINVAL The  fd argument is valid but not associated with a master pseu‐
34              doterminal.
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VERSIONS

37       grantpt() is provided in glibc since version 2.1.
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CONFORMING TO

40       POSIX.1-2001.
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NOTES

43       This is part of the UNIX 98 pseudoterminal support, see  pts(4).   Many
44       systems  implement this function via a set-user-ID helper binary called
45       "pt_chown".  With Linux devpts no such helper binary is required.
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COLOPHON

51       This page is part of release 3.53 of the Linux  man-pages  project.   A
52       description  of  the project, and information about reporting bugs, can
53       be found at http://www.kernel.org/doc/man-pages/.
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57GNU                               2008-06-14                        GRANTPT(3)