Originální popis anglicky:
fchmod - change mode of a file
Návod, kniha: POSIX Programmer's Manual
#include <sys/stat.h>
int fchmod(int
fildes, mode_t
mode );
The
fchmod() function shall be equivalent to
chmod() except that
the file whose permissions are changed is specified by the file descriptor
fildes.
If
fildes references a shared memory object, the
fchmod() function
need only affect the S_IRUSR, S_IWUSR, S_IRGRP, S_IWGRP, S_IROTH, and S_IWOTH
file permission bits.
If
fildes references a typed memory object, the behavior of
fchmod() is unspecified.
If
fildes refers to a socket, the behavior of
fchmod() is
unspecified.
If
fildes refers to a STREAM (which is
fattach()-ed into the file
system name space) the call returns successfully, doing nothing.
Upon successful completion,
fchmod() shall return 0. Otherwise, it shall
return -1 and set
errno to indicate the error.
The
fchmod() function shall fail if:
- EBADF
- The fildes argument is not an open file
descriptor.
- EPERM
- The effective user ID does not match the owner of the file
and the process does not have appropriate privilege.
- EROFS
- The file referred to by fildes resides on a
read-only file system.
The
fchmod() function may fail if:
- EINTR
- The fchmod() function was interrupted by a
signal.
- EINVAL
- The value of the mode argument is invalid.
- EINVAL
- The fildes argument refers to a pipe and the
implementation disallows execution of fchmod() on a pipe.
The following sections are informative.
The following example shows how to change the permissions for a file named
/home/cnd/mod1 so that the owner and group have read/write/execute
permissions, but the world only has read/write permissions.
#include <sys/stat.h>
#include <fcntl.h>
mode_t mode;
int fildes;
...
fildes = open("/home/cnd/mod1", O_RDWR);
fchmod(fildes, S_IRWXU | S_IRWXG | S_IROTH | S_IWOTH);
None.
None.
None.
chmod() ,
chown() ,
creat() ,
fcntl() ,
fstatvfs() ,
mknod() ,
open() ,
read() ,
stat() ,
write() , the Base Definitions volume of
IEEE Std 1003.1-2001,
<sys/stat.h>
Portions of this text are reprinted and reproduced in electronic form from IEEE
Std 1003.1, 2003 Edition, Standard for Information Technology -- Portable
Operating System Interface (POSIX), The Open Group Base Specifications Issue
6, Copyright (C) 2001-2003 by the Institute of Electrical and Electronics
Engineers, Inc and The Open Group. In the event of any discrepancy between
this version and the original IEEE and The Open Group Standard, the original
IEEE and The Open Group Standard is the referee document. The original
Standard can be obtained online at http://www.opengroup.org/unix/online.html
.
