identifies an external
file. If fileref is a literal
fileref name, it must be in quotation marks. If fileref is
the name of a character variable whose value is a fileref name, it
must not be quoted. Under z/OS, it can be a fileref or any valid ddname
that has been previously associated with an external file with either
a TSO ALLOCATE command or a JCL DD statement. In a DATA step, fileref can
be a character expression, a string enclosed in quotation marks, or
a DATA step variable whose value contains the fileref. In a macro, fileref can
be any expression. For information about the values returned by this
function, see FEXIST Function in SAS Functions and CALL Routines: Reference in the SAS Functions and CALL Routines: Reference.
Details
FEXIST returns 1 if
the external file that is associated with fileref exists, and 0 if
the file does not exist.