Shareware Grab Bag/Shareware Grab Bag.iso/090/wheels1.arc/EXISTFIL.LIB

Text File | 1985-06-28 | 1KB | 31 lines

{@@@@@@@@@@@ copyright (C) 1984 by Neil J. Rubenking @@@@@@@@@@@@@@@@@@@@@@@@
The purchaser of these procedures and functions may include them in COMPILED
programs freely, but may not sell or give away the source text.

This function checks for the existence of a file of the name passed to it
by attempting to reset the file with I/O error checking switched off, and
then looking at IOResult, the built-in variable that holds I/O error
messages.  This function will NOT check for files in any but the current
directory--use the "Find_First" function in GETFILE.LIB for those.

function EXISTS: boolean;
  input : a filename of a TYPE declared in user program (BEFORE including this
              file!)
  output: true if exists else false.

@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@}

function exists(ThisFile : old_filename_Type):boolean;
var
  tempFile : text;  {We can get away with assigning a text file to ANY
                     filename because we aren't going to do any input/output}
begin
  assign(tempFile,ThisFile);
  {$I-}
  reset(tempFile);
  {$I+}
  if IOResult = 0 then exists := true
    else exists := false;
  close(tempFile);
end;