MPE::File - Perl extension for accessing MPE File intrinsics


  use MPE::File;
  $file = MPE::File->new("FRED.PUB,old;acc=in")
    or die "Cannot open FRED.PUB: $MPE_error\n";
  $file = MPE::File->hpfopen(2, "FRED.PUB", 3, 1, 11, 0)
    or die "Cannot open FRED.PUB: $MPE_error\n";
  $file = MPE::File->fopen("FRED.PUB", 1, 0)
    or die "Cannot open FRED.PUB: $MPE_error\n";
  $rec = $file->readrec();   # use this instead of fread
  $rec = $file->freadbykey($key, $keyloc);
  $rec = $file->freadlabel( [$labelid] );
  $rec = $file->freaddir($lrecnum);
  $rec = $file->freadc();
  $file->fread($buffer, $bufsize);
  $file->writerec($buffer, [$controlcode] )   # use this instead of fwrite
  $file->fwritedir($buffer, $lrecnum);
  $file->fwritelabel ($buffer, [$labelid] )
  $file->fwrite($buffer, $length, $controlcode)
  $file->fcontrol($itemnum, $item);
  $file->fdelete( [$lrecnum] );
  $file->fgetkeyinfo($param, $control);
  $file->ffindbykey($value, $location, $length, $relop);
  @info = $file->ffileinfo(1, 3, 7, 9);
  @info = flabelinfo("FRED.PUB", $mode, 1, 3, 7, 9);
  $errmsg = ferrmsg($fserrcode);


  The primary reference should be the MPE/iX Intrinsic Reference Manual
  (available at
  Notice that there are some difference in parameters.
  For example, I take care of all the delimited strings in HPFOPEN
  Subroutines return 0 or undef on failure; check $MPE_error for
  the error number and/or string (both should be valid).
  MPE::File->new($x) is the same as MPE::File->hpfopen(52, $x)
  which, to quote the Intrinsic manual:
    "Passes a character string that matches the file equation
    specification syntax exactly."
  You can pass other HPFOPEN parameter pairs after the first
  one, although almost all can be specified in the file equation.

  One that can't be is to save a file right away, on HPFOPEN, instead
  of waiting until FCLOSE.  You can do that like this:
  $file = MPE::File->new("FRED,new;rec=-80,,f,ascii;msg;acc=in", 3, 4)
     or die "Cannot open FRED: $MPE_error\n";
  (Notice the 3, 4 pair at the end.)
  If you use FFREADBYKEY, remember to pad out your keys to the full
  length.  Also, if they are binary keys, you'll need to use pack,
  otherwise a number will be converted to its string equivalent.
  This documentation will be expanded at some point; feel free to
  send me suggestions (or completed paragraphs).


flabelinfo $MPE_error


Ken Hirsch <>

This module may be used and distributed on the same terms as Perl.