[character(1)]
Name for x. Defaults to a heuristic to determine
the name using deparse and substitute.
access
[character(1)]
Single string containing possible characters r, w and x to
force a check for read, write or execute access rights, respectively.
Value
Depending on the function prefix:
If the check is successful, all functions return TRUE.
If the check is not successful, assertAccess throws an error message,
testAccess returns FALSE and checkAccess returns
a string with the error message.