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NAME | LIBRARY | SYNOPSIS | DESCRIPTION | RETURN VALUE | VERSIONS | STANDARDS | HISTORY | SEE ALSO | COLOPHON |
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KEYCTL_SET_TIMEOUT(2const) KEYCTL_SET_TIMEOUT(2const)
KEYCTL_SET_TIMEOUT - set the expiration timer on a key
Standard C library (libc, -lc)
#include <linux/keyctl.h> /* Definition of KEY* constants */
#include <sys/syscall.h> /* Definition of SYS_* constants */
#include <unistd.h>
long syscall(SYS_keyctl, KEYCTL_SET_TIMEOUT, key_serial_t key, time_t t);
Set a timeout on a key.
The ID of the key is specified in key. The timeout value, in
seconds from the current time, is specified in t. The timeout is
measured against the realtime clock.
Specifying the timeout value as 0 clears any existing timeout on
the key.
The /proc/keys file displays the remaining time until each key
will expire. (This is the only method of discovering the timeout
on a key.)
The caller must either have the setattr permission on the key or
hold an instantiation authorization token for the key (see
request_key(2)).
The key and any links to the key will be automatically garbage
collected after the timeout expires. Subsequent attempts to
access the key will then fail with the error EKEYEXPIRED.
This operation cannot be used to set timeouts on revoked, expired,
or negatively instantiated keys.
On success, 0 is returned.
On error, -1 is returned, and errno is set to indicate the error.
A wrapper is provided in the libkeyutils library:
keyctl_set_timeout(3).
Linux.
Linux 2.6.16.
keyctl(2), keyctl_set_timeout(3)
This page is part of the man-pages (Linux kernel and C library
user-space interface documentation) project. Information about
the project can be found at
⟨https://www.kernel.org/doc/man-pages/⟩. If you have a bug report
for this manual page, see
⟨https://git.kernel.org/pub/scm/docs/man-pages/man-pages.git/tree/CONTRIBUTING⟩.
This page was obtained from the tarball man-pages-6.15.tar.gz
fetched from
⟨https://mirrors.edge.kernel.org/pub/linux/docs/man-pages/⟩ on
2025-08-11. If you discover any rendering problems in this HTML
version of the page, or you believe there is a better or more up-
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improvements to the information in this COLOPHON (which is not
part of the original manual page), send a mail to
man-pages@man7.org
Linux man-pages 6.15 2025-05-17 KEYCTL_SET_TIMEOUT(2const)
Pages that refer to this page: keyctl(2)
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HTML rendering created 2025-09-06 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. |
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