Python os.access() Method

Description

The method access() uses the real uid/gid to test for access to path. Most operations will use the effective uid/gid, therefore this routine can be used in a suid/sgid environment to test if the invoking user has the specified access to path.It returns True if access is allowed, False if not.

Syntax

Following is the syntax for access() method

os.access(path, mode);

Parameters

• path -- This is the path which would be tested for existence or any access.

• mode -- This should be F_OK to test the existence of path, or it can be the inclusive OR of one or more of R_OK, W_OK, and X_OK to test permissions.

  • os.F_OK: Value to pass as the mode parameter of access() to test the existence of path.
  • os.R_OK: Value to include in the mode parameter of access() to test the readability of path.
  • os.W_OK Value to include in the mode parameter of access() to test the writability of path.
  • os.X_OK Value to include in the mode parameter of access() to determine if path can be executed.

Return Value

This method returns True if access is allowed, False if not.

Example

The following example shows the usage of access() method.

#!/usr/bin/python

import os, sys

# Assuming /tmp/foo.txt exists and has read/write permissions.

ret = os.access("/tmp/foo.txt", os.F_OK)
print "F_OK - return value %s"% ret

ret = os.access("/tmp/foo.txt", os.R_OK)
print "R_OK - return value %s"% ret

ret = os.access("/tmp/foo.txt", os.W_OK)
print "W_OK - return value %s"% ret

ret = os.access("/tmp/foo.txt", os.X_OK)
print "X_OK - return value %s"% ret

Let us compile and run the above program, this will produce the following result:

F_OK - return value True
R_OK - return value True
W_OK - return value True
X_OK - return value False