Differences between current version and predecessor to the previous major change of fchmod(2).
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| Newer page: | version 4 | Last edited on Thursday, October 31, 2002 10:21:28 pm | by JohnMcPherson | |
| Older page: | version 1 | Last edited on Tuesday, June 4, 2002 12:23:40 am | by perry | Revert |
@@ -1,265 +1,63 @@
CHMOD
-!!!CHMOD
-NAME
-SYNOPSIS
-DESCRIPTION
-RETURN VALUE
-ERRORS
-CONFORMING TO
-SEE ALSO
-----
-!!NAME
+!!NAME
-chmod,
fchmod - change permissions of a file
+fchmod - change permissions of a file
!!SYNOPSIS
+ __#include <sys/stat.h>__
+ __#include <sys/types.h>__
-__#include __
-#include __
+ __int fchmod(int__ ''fildes''__, mode_t__ ''mode''__);__
-__int chmod(const char *__''path''__, mode_t__
-''mode''__);
-int fchmod(int__ ''fildes''__, mode_t__
-''mode''__);__
!!DESCRIPTION
-The mode of the file given by ''path'' or
referenced by
-
+The mode of the file referenced by ''fildes'' is changed.
-Modes are specified by ''or'ing'' the
-
+Modes are specified by ''or'ing'' the following:
+|S_ISUID|04000|set user ID on execution
+|S_ISGID|02000|set group ID on execution
+|S_ISVTX|01000|sticky bit
+|S_IRUSR (S_IREAD)|00400|read by owner
+|S_IWUSR (S_IWRITE)|00200|write by owner
+|S_IXUSR (S_IEXEC)|00100|execute/search by owner
+|S_IRGRP|00040|read by group
+|S_IWGRP|00020|write by group
+|S_IXGRP|00010|execute/search by group
+|S_IROTH|00004|read by others
+|S_IWOTH|00002|write by others
+|S_IXOTH|00001|execute/search by others
+The effective UID of the process must be zero or must match the owner of the file.
-S_ISUID
+If the effective UID of the process is not zero and the group of the file does not match the effective group ID of the process or one of its supplementary group IDs, the
S_ISGID bit will be turned off, but this will not cause an error to be returned.
+Depending on the file system, set user ID and set group ID execution bits may be turned off if a file is written. On some file systems, only the super-user can set the sticky bit, which may have a special meaning. For the sticky bit, and for set user ID and set group ID bits on directories, see stat(2).
-04000 set user ID
on execution
+On NFS file systems, restricting the permissions will immediately influence already open files, because the access control is done
on the server, but open files are maintained by the client. Widening the permissions may be delayed for other clients if attribute caching is enabled on them.
-
-S_ISGID
-
-
-02000 set group ID on execution
-
-
-S_ISVTX
-
-
-01000 sticky bit
-
-
-S_IRUSR (S_IREAD)
-
-
-00400 read by owner
-
-
-S_IWUSR (S_IWRITE)
-
-
-00200 write by owner
-
-
-S_IXUSR (S_IEXEC)
-
-
-00100 execute/search by owner
-
-
-S_IRGRP
-
-
-00040 read by group
-
-
-S_IWGRP
-
-
-00020 write by group
-
-
-S_IXGRP
-
-
-00010 execute/search by group
-
-
-S_IROTH
-
-
-00004 read by others
-
-
-S_IWOTH
-
-
-00002 write by others
-
-
-S_IXOTH
-
-
-00001 execute/search by others
-
-
-The effective UID of the process must be zero or must match
-the owner of the file.
-
-
-If the effective UID of the process is not zero and the
-group of the file does not match the effective group ID of
-the process or one of its supplementary group IDs, the
-S_ISGID bit will be turned off, but this will not cause an
-error to be returned.
-
-
-Depending on the file system, set user ID and set group ID
-execution bits may be turned off if a file is written. On
-some file systems, only the super-user can set the sticky
-bit, which may have a special meaning. For the sticky bit,
-and for set user ID and set group ID bits on directories,
-see stat(2).
-
-
-On NFS file systems, restricting the permissions will
-immediately influence already open files, because the access
-control is done on the server, but open files are maintained
-by the client. Widening the permissions may be delayed for
-other clients if attribute caching is enabled on
-them.
!!RETURN VALUE
+On success, zero is returned. On error, -1 is returned, and ''errno'' is set appropriately.
-On success, zero is returned. On error, -1 is returned, and
-''errno'' is set appropriately.
!!ERRORS
+Depending on the file system, other errors can be returned. The more general errors for __chmod__ are listed below:
-Depending on the file system, other errors can be returned.
-The more general errors for __chmod__ are listed
-below
:
-
-
-__EPERM__
-
-
-
-
-
-
-__
EROFS__
-
-
-
-
-
-
-__EFAULT__
-
-
-''path'' points outside your accessible address
-space.
-
-
-__ENAMETOOLONG__
-
-
-''path'' is too long.
-
-
-__ENOENT__
-
-
-The file does not exist.
-
-
-__
ENOMEM__
-
-
-
-
-
-__
ENOTDIR__
-
-
-
-
-
-
-__EACCES__
-
-
-Search permission is denied on a component of the path
-prefix.
-
-
-__ELOOP__
-
-
-Too many symbolic links were encountered in resolving
-''path''.
-
-
-__
EIO__
-
-
-
-
-
-The general errors for __fchmod__ are listed
-below
:
-
-
-__EBADF__
-
-
-.
-
-
-__EROFS__
-
-
-See above.
-
-
-__EPERM__
-
-
-See above.
-
-
-__EIO__
-
-
-See above
.
+;[EPERM]
: The effective UID does not match the owner of the file, and is not zero.
+;[
EROFS]:
The named file resides on a read-only file system.
+;[
ENOMEM]:
Insufficient kernel memory was available.
+;[
ENOTDIR]:
A component of the path prefix is not a directory.
+;[
EIO]:
An I/O error occurred.
+;[EBADF]
: The file descriptor ''fildes'' is not valid.
!!CONFORMING TO
+The fchmod(2) call conforms to 4.4BSD and SVr4. SVr4 documents additional [EINTR] and [ENOLINK] error conditions. POSIX requires the fchmod(2) function if at least one of POSIX_MAPPED_FILES and _POSIX_SHARED_MEMORY_OBJECTS is defined, and documents additional [ENOSYS] and [EINVAL] error conditions, but does not document [EIO].
-The __chmod__ call conforms to SVr4, SVID, POSIX, X/OPEN,
-4.4BSD. SVr4 documents EINTR, ENOLINK and EMULTIHOP returns,
-but no ENOMEM. POSIX.1 does not document EFAULT, ENOMEM,
-ELOOP or EIO error conditions, or the macros __S_IREAD__,
-__S_IWRITE__ and __S_IEXEC__.
-
-
-The __fchmod__ call conforms to 4.4BSD and SVr4. SVr4
-documents additional EINTR and ENOLINK error conditions.
-POSIX requires the __fchmod__ function if at least one of
-___POSIX_MAPPED_FILES__ and
-___POSIX_SHARED_MEMORY_OBJECTS__ is defined, and
-documents additional ENOSYS and EINVAL error conditions, but
-does not document EIO.
-
-
-
-
+[
POSIX]
and X/OPEN do not document the sticky bit.
!!SEE ALSO
-
-
-
-----
+open(2), chown(2), execve(2), stat(2)
