Home Man
Search
Today's Posts
Register

Linux & Unix Commands - Search Man Pages

OpenDarwin 7.2.1 - man page for access (opendarwin section 2)

ACCESS(2)			     BSD System Calls Manual				ACCESS(2)

NAME
     access -- check access permissions of a file or pathname

SYNOPSIS
     #include <unistd.h>

     int
     access(const char *path, int mode);

DESCRIPTION
     The access() function checks the accessibility of the file named by path for the access per-
     missions indicated by mode.  The value of mode is the bitwise inclusive OR of the access
     permissions to be checked (R_OK for read permission, W_OK for write permission and X_OK for
     execute/search permission) or the existence test, F_OK.  All components of the pathname path
     are checked for access permissions (including F_OK).

     The real user ID is used in place of the effective user ID and the real group access list
     (including the real group ID) are used in place of the effective ID for verifying permis-
     sion.

     Even if a process has appropriate privileges and indicates success for X_OK, the file may
     not actually have execute permission bits set.  Likewise for R_OK and W_OK.

RETURN VALUES
     If path cannot be found or if any of the desired access modes would not be granted, then a
     -1 value is returned; otherwise a 0 value is returned.

ERRORS
     Access to the file is denied if:

     [ENOTDIR]		A component of the path prefix is not a directory.

     [ENAMETOOLONG]	A component of a pathname exceeded {NAME_MAX} characters, or an entire
			path name exceeded {PATH_MAX} characters.

     [ENOENT]		The named file does not exist.

     [ELOOP]		Too many symbolic links were encountered in translating the pathname.

     [EROFS]		Write access is requested for a file on a read-only file system.

     [ETXTBSY]		Write access is requested for a pure procedure (shared text) file
			presently being executed.

     [EACCES]		Permission bits of the file mode do not permit the requested access, or
			search permission is denied on a component of the path prefix.	The owner
			of a file has permission checked with respect to the ``owner'' read,
			write, and execute mode bits, members of the file's group other than the
			owner have permission checked with respect to the ``group'' mode bits,
			and all others have permissions checked with respect to the ``other''
			mode bits.

     [EFAULT]		Path points outside the process's allocated address space.

     [EIO]		An I/O error occurred while reading from or writing to the file system.

     [EINVAL]		An invalid value was specified for mode.

SEE ALSO
     chmod(2), stat(2)

STANDARDS
     The access() function conforms to ISO/IEC 9945-1:1990 (``POSIX.1'').

CAVEAT
     Access() is a potential security hole and should never be used.

4th Berkeley Distribution		  April 1, 1994 		4th Berkeley Distribution


All times are GMT -4. The time now is 02:21 AM.

Unix & Linux Forums Content Copyrightę1993-2018. All Rights Reserved.
UNIX.COM Login
Username:
Password:  
Show Password