Subj : sweep
To   : Vitus Jensen
From : Eddy Thilleman
Date : Thu Mar 15 2001 03:55 am

Hello Vitus,

Wednesday 14 March 2001 02:18, Vitus Jensen wrote to Eddy Thilleman:

ET>>>> Borland Pascal as DOS .EXE file and compiled it with Virtual
ET>>>> Pascal/2 v2.1 build 243 as OS/2 .EXE file, and implemented it
ET>>>> also in REXX.
VJ> ...
ET>> another example

ET>> sweep for %a in (*.bak) do echo %a

ET>> The compiled version is easier to use than the REXX variant.

VJ> "easier to use"?  I would expect the rexx variant to be easier to
VJ> code.

Yep, that's the difference. The REXX variant is somewhat easier to code (the 
pascal version is not difficult), but I found it more difficult to use the REXX 
variant with a "for %a in (*) do..." command (with and without a preceding 'cmd 
/c'), because sometimes I get errors, like:

C:\>\os2\rexx\sweep for %a in (*.txt) do echo %a
>> Command >> for %a in (*.txt) do echo %a
>>> Sweep >>> C:\
SYS1079: a was unexpected at this time.
Error?  rc=1

C:\>\os2\rexx\sweep cmd /c for %a in (*.txt) do echo %a
>> Command >> cmd /c for %a in (*.txt) do echo %a
>>> Sweep >>> C:\
SYS1079: a was unexpected at this time.
Error?  rc=1

C:\>\os2\rexx\sweep cmd /c for %%a in (*.txt) do echo %%a
>> Command >> cmd /c for %%a in (*.txt) do echo %%a
>>> Sweep >>> C:\
Error?  rc=31112

C:\>\os2\rexx\sweep cmd /c for %a in (*.txt) do echo %a
>> Command >> cmd /c for %a in (*.txt) do echo %a
>>> Sweep >>> C:\
SYS1079: a was unexpected at this time.
Error?  rc=1


Only one time I managed to get above construct working with the REXX variant. 
That's why I wrote the pascal version.

ET>>>> Shall I post the source of all three?
VJ>>> Are you sure it's the screen output?
ET>> No, I'm not certain.
VJ>>> If not, remove screen output from the program and rerun it.

ET>> I've run it without screen output from all the sweep variants
ET>> themselves, the only screen output is by the command run in each
ET>> (sub)directory. The command in the compiled OS/2 version is run
ET>> somewhat slower.

VJ> There are larger gaps between execution in the different directories?

Yes.

VJ> That would mean that searching for directories is slower in VP/2
VJ> which is not to be expected or the startup of every command line takes
VJ> longer (s.b.).

I'm not sure about this.

VJ> (how do you do it?),

FindFirst/FindNext.

Here is the source code of the pascal version:

------------------- begin of sweep.pas -------------------

uses dos;

Var
  i       : byte;
  quiet   : boolean;
  CmdProc : string;
  CmdLine : string;


function RunProg( Prog, Parm: string ): boolean;
begin
  Exec( Prog, Parm );
  if DOSError = 0 then
    RunProg := True
  else
    writeln( 'DOS error #', DOSError );
end;


{$S+}
Procedure AllDirs;
var
  DR : SearchRec;
  Pad: string;

begin
  GetDir( 0, Pad );
  if not quiet then writeln( '>>> SWEEP >>> ' + Pad );
  if RunProg( CmdProc, '/c' + CmdLine ) then
  begin
    FindFirst('*', Directory, DR);
    while (DosError = 0) do
    begin
      if (DR.Attr and Directory) = Directory then
      begin
        if ((DR.Name <> '.') and (DR.Name <> '..')) then
        begin
          ChDir( DR.Name );
          AllDirs;
          ChDir( '..' );
        end
      end;
      FindNext( DR );
    end;
  end;
end;
{$S-}

begin
  quiet := False;
  if ParamCount > 0 then begin
    CmdProc := GetEnv('COMSPEC');
    CmdLine := '';
    for i := 1 to ParamCount do
    begin
      if ((paramstr( i )[1] = '/') or (paramstr( i )[1] = '-')) and 
(upcase(paramstr( i )[2]) = 'Q') then
        quiet := True
      else
        CmdLine := CmdLine + ' ' + paramstr( i );
      { /q ? }
    end;  { all parameters }
    writeln( 'command:', CmdLine );
    AllDirs;
  end;
end.
-------------------- end of sweep.pas --------------------

VJ> cmd.exe should already reside in the disk cache so the difference
VJ> should be small or non existent.

VJ> You are executing all commands through cmd.exe when coding in pascal.
VJ> How do you do it in Rexx?

Here is the source code for the REXX variant:

------------------- begin of sweep.cmd -------------------
/*
 * A sweep command for OS/2
 * Recurses through directories from default and executes a command line
*/

'@echo off'

ARG P1 dummy

if P1 = '-Q' then
  parse arg dummy cl
else do
  P1 = 0
  parse arg cl
end

if cl = '/?' then signal GiveHelp
if cl = '?'  then signal GiveHelp
if cl = '-?' then signal GiveHelp
if cl = ''   then signal GiveHelp

signal on Syntax
signal on Error
signal on Failure
signal on Halt

CRLF = '0D'x || '0A'x

n = setlocal()

say '>> Command >>' cl
call Exec( directory() )

n = endlocal()
return


Exec: procedure expose cl P1
  parse arg path

  newdir = directory( path )
  if newdir = path then
  do
    if P1 \= '-Q' then say '>>> Sweep >>>' directory()
    cl
  end

  Call SysFileTree path || "\*", 'dir', 'D'
  if datatype( dir.0 ) <> "NUM" then dir.0 = 0
  do f = 1 to dir.0
    name = substr( dir.f, 38 )
    if (substr( dir.f, 32, 1 ) = 'D') then    /* directory? */
      call Exec( name )
  end
return


Syntax:
  ErrorNr = rc
  Say 'Line' sigl':' Sourceline(sigl)
  Say 'Error' rc':' Errortext(ErrorNr)
  n = endlocal()
  exit


Failure:
  say 'Failure, rc='rc
  n = endlocal()
  exit


Error:
  say 'Error?  rc='rc
  n = endlocal()
  exit


Halt:
  n = endlocal()
  exit


GiveHelp:
  say 'SWEEP.CMD'
  say ' Performs a command in the current directory and in all its 
subdirectories.'
  say ''
  say ' Usage:    Sweep [-Q] command'
  say ''
  say '                  -Q  quiet, don''t display directories'
  exit
-------------------- end of sweep.cmd --------------------

VJ> If you just let the already running copy of cmd.exe handle it we have
VJ> a major difference: a new process for cmd.exe does not have to be
VJ> started. Try to compare the following times,

The DOS pascal version is equally fast as the REXX version, the OS/2 VP/2 
version is slower (as I said).

VJ> Rexx:        sweep cmd /C "for %a in (*.bak) do echo %a"

I can't execute this with the REXX version. single commands work with the REXX 
version, however.

That's why I just give cd as the single command to all sweep versions.

VJ> Pascal:      sweep for %a in (*.bak) do echo %a

for the pascal version, this is no problem.

Any ideas?


  Greetings   -=Eddy=-

  email: e.thilleman@freeler.nl
         e.thilleman@hccnet.nl

.... Warp 4, Scotty... and close those damn Windows!
--- GoldED/2 3.0.1
 * Origin: The only thing more complicated than computers is TAX (2:280/5143.7)

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