chown

chown

Change File Owner or Group (Using Pathname)

Portability: POSIX.1 conforming, UNIX compatible

SYNOPSIS
DESCRIPTION
RETURN VALUE
EXAMPLE
RELATED FUNCTIONS

SYNOPSIS

#include <unistd.h>

int chown(const char *pathname, uid_t owner, gid_t group);

DESCRIPTION

chown changes the owner or owning group of a file. It can be used with either regular files or special files, such as directories or FIFO files. pathname is the name of the file. owner is the user ID. group is the group ID.

USS implements a restricted chown for all files. A call to chown can succeed in only one of two ways:

the caller is a superuser
the effective user ID is the same as the owner of the file, which is equal to the owner argument to chown , and the group argument is the effective group ID or one of the user's supplementary IDs.

If the S_IXUSR , S_IXGRP , or S_IXOTH bit is set in the file permissions, chown clears the S_ISUID and S_ISGID bits of the permissions.

RETURN VALUE

chown returns 0 if successful and a -1 if not successful.

EXAMPLE

The following example illustrates the use of chown to change a file's owner and group:

#include <sys/types.h>
#include <unistd.h>
#include <grp.h>
#include <stdlib.h>

main(int argc, char *argv[])
{
   struct group *billing;
   int rc;

   billing = getgrnam("BILLING");
   if (!billing) {
      perror("getgrnam error");
      abort();
   }
   if (argc <= 1) {
      printf("No file name specified.\\n");
      exit(EXIT_FAILURE);
   }
   rc = chown(argv[1], geteuid(), billing->gr_gid);
   if (rc == 0) {
      printf("Ownership of %s assigned to BILLING.\\n", argv[1]);
      exit(EXIT_SUCCESS);
   }
   else {
      perror("chown error");
      abort();
   }
}

RELATED FUNCTIONS

chmod , fchown

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