09-28-2009
Quote:
Originally Posted by
jim mcnamara
Nice tip! Didn't think of that.
Thanks.
Although it's four functions and not only two. Thus means
two arrays of pointers.
Interesting solution anyway.
S.
---------- Post updated at 01:48 AM ---------- Previous update was at 01:46 AM ----------
Quote:
Originally Posted by
Corona688
Are you typing up these responses in another program then copy-pasting? You don't need to do that, it adds pointless extra linebreaks. The text will wrap by itself when it needs to.
I'm not copying-and-pasting anything.
Quote:
Originally Posted by
Corona688
The performance difference between a function pointer and if/else is not going to be significant here, use whatever is clearest. If it was a choice between three or more functions, a function pointer might be more efficient and elegant.
The point is that the function is called _VERY_ often, so the more is optimized, the better.
Thanks for the advice.
S.
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LEARN ABOUT CENTOS
keyctl_update
KEYCTL_UPDATE(3) Linux Key Management Calls KEYCTL_UPDATE(3)
NAME
keyctl_update - Update a key
SYNOPSIS
#include <keyutils.h>
long keyctl_update(key_serial_t key, const void *payload,
size_t plen);
DESCRIPTION
keyctl_update() updates the payload of a key if the key type permits it.
The caller must have write permission on a key to be able update it.
payload and plen specify the data for the new payload. payload may be NULL and plen may be zero if the key type permits that. The key
type may reject the data if it's in the wrong format or in some other way invalid.
RETURN VALUE
On success keyctl_update() returns 0. On error, the value -1 will be returned and errno will have been set to an appropriate error.
ERRORS
ENOKEY The key specified is invalid.
EKEYEXPIRED
The key specified has expired.
EKEYREVOKED
The key specified had been revoked.
EINVAL The payload data was invalid.
ENOMEM Insufficient memory to store the new payload.
EDQUOT The key quota for this user would be exceeded by increasing the size of the key to accommodate the new payload.
EACCES The key exists, but is not writable by the calling process.
EOPNOTSUPP
The key type does not support the update operation on its keys.
LINKING
This is a library function that can be found in libkeyutils. When linking, -lkeyutils should be specified to the linker.
SEE ALSO
keyctl(1),
add_key(2),
keyctl(2),
request_key(2),
keyctl(3),
request-key(8)
Linux 4 May 2006 KEYCTL_UPDATE(3)