access - determine accessability of a file
integer function access (name, mode)
character*(*) name, mode
Access checks the given file, name, for accessability with respect to
the caller according to mode. Mode may include in any order and in any
combination one or more of:
r test for read permission
w test for write permission
x test for execute permission
(blank) test for existence
An error code is returned if either argument is illegal, or if the file
can not be accessed in all of the specified modes. 0 is returned if
the specified access would be successful.
Pathnames can be no longer than MAXPATHLEN as defined in <sys/param.h>.
4th Berkeley Distribution 26 July 1983 ACCESS(3F)