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KEYCTL_DESCRIBE(3)        Linux Key Management Calls        KEYCTL_DESCRIBE(3)
NAME
       keyctl_describe - describe a key
SYNOPSIS
       #include <keyutils.h>
       long keyctl_describe(key_serial_t key, char *buffer,
       size_tbuflen);
       long keyctl_describe_alloc(key_serial_t key, char **_buffer);
DESCRIPTION
       keyctl_describe() describes the attributes of a key as a NUL-terminated
       string.
       The caller must have view permission on a key  to  be  able  to  get  a
       description of it.
       buffer  and  buflen  specify  the buffer into which the key description
       will be placed.  If the buffer is too  small,  the  full  size  of  the
       description will be returned, and no copy will take place.
       keyctl_describe_alloc()  is similar to keyctl_describe() except that it
       allocates a buffer big enough to hold the description  and  places  the
       description in it.  If successful, A pointer to the buffer is placed in
       *_buffer.  The caller must free the buffer.
       The description will be a string of format:
              "%s;%d;%d;%08x;%s"
       where the arguments are: key type name, key UID, key GID,  key  permis-
       sions mask and key description.
       NOTE!   The  key  description  will not contain any semicolons, so that
       should be separated out by  working  backwards  from  the  end  of  the
       string.   This  permits  extra  information to be inserted before it by
       later versions of the kernel simply by inserting more  semicolon-termi-
       nated substrings.
RETURN VALUE
       On success keyctl_describe() returns the amount of data placed into the
       buffer.  If the buffer was too small, then the size of buffer  required
       will be returned, but no data will be transferred.  On error, the value
       -1 will be returned and errno will have  been  set  to  an  appropriate
       error.
       On  success  keyctl_describe_alloc()  returns the amount of data in the
       buffer, less the NUL terminator.   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              The key specified had been revoked.
       EACCES The key exists, but is not viewable by the calling process.
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),
       keyrings(7), keyutils(7)
Linux                             4 May 2006                KEYCTL_DESCRIBE(3)