Why no pipes?

[Erich Schulman]

The manual makes it clear that STDIN/STDOUT do not support piping. Was that perhaps just a performance decision?

So that I am not forced to use C++ or Python for pipes, are there any examples of implementing pipes via API calls?

[Dave Biggs]

See the 'ShellConsoleApp' function in David's code..

http://www.powerbasic.com/support/pbforums/showthread.php?t=24480

That credits code posted by Semen (probably here)..

http://www.powerbasic.com/support/pbforums/showpost.php?p=137411&postcount=1

[Michael Mattias]

Piping sends to STDIN of the target app.

Both createprocess() and shellexecuteex() can start a process with an override for the STDIN (and/or STDOUT and/or STDERR) of that target process.

However, it is the responsibility of the target application to use any overrides provided; the GetStartupInfo() or GetStdHandle() functions may be used to obtain the redirected standard handles.

I have not tried with 5x, but I had problems with PB/CC up thru 4x respecting those overrides. I never had a problem when PB/Windows was used to create the child application.


MCM

[Erich Schulman]

If I use GetStdHandle to get the stdin handle, will PB statements be able to use the handle, or do I need ReadConsoleInput to get what is being piped to me?

[Michael Mattias]

If your application is the target of an application which pipes its output to your application - that is, your STDIN - I don't think you would need to use GetStdHandle() at all.... I would think STDIN would work.... after all, aren't "CGI" applications based on this principle?

You might try using one of the "CGI" samples provided with the compiler as the basis for a test program to see if that does the job.

MCM

PS: we "are" speaking of "command-line" piping here, right? eg...

C:\DOS>  ProgA.exe | progB.exe

.. where "ProgB" is your program.

Because if we are talking about Windows pipe objects, there is no problem at all using those with either flavor of compiler.

[Michael Mattias]

then again, if ...

C:\DOS>  ProgA.exe | progB.exe

.. works, so would

C:\DOS>  ProgA.exe > Filename
C:\DOS>  ProgB.exe < Filename

MCM

[Michael Mattias]

Ignoring the title, this...

Wait for key, click or clock for PB/WIN and PB/CC

... shows you how to efficiently obtain and process input to your program's stdin.

MCM

[Erich Schulman]

PS: we "are" speaking of "command-line" piping here, right? eg...

C:\DOS>  ProgA.exe | progB.exe

.. where "ProgB" is your program.

Because if we are talking about Windows pipe objects, there is no problem at all using those with either flavor of compiler.

I want to be prepared to be anywhere in the pipeline, so I could be both source and target.

find (something) | sed (something) | myprog (something) | grep (something) > finalresult.txt

Long pipelines are probably rare in Windows, but when you have Cygwin and Unix/Linux experience, you become more likely to use them.

[Michael Mattias]

find (something) | sed (something) [COLOR="Red"]| myprog (something) |[/COLOR] grep (something) > finalresult.txt

I'm not sure you can use that syntax to be SOURCE (in this case to grep) but I'd sure give it a try by using one of the CGI samples as a starter program.

I'm pretty sure using STDIN as your input (like the CGI samples) will work when you are the target (from sed); on the source side, simply sending your output to STDOUT just might work, but that one I'm not so confident in. I know you could make it work using CreateProcess(), but that would not be fun to handle in the command-line at all, since now the "|" coming out of "myprog" would have to be treated as some kind of input parameter.

But I'd try the STDIN/STDOUT approach first anyway.

If you have PB/CC 4 or greater, I think I'd look at using the "no console" directive when compiling. IIRC the problems I encountered were that when a PB/CC program starts, it makes its console the STDIN/STDOUT regardless of other instructions received.

If I didn't have to do this other thing (that food, clothing, shelter thing) today, this sounds like a fun project.

MCM

[Erich Schulman]

The docs say

Restrictions
 STDIN LINE does not work with pipes.
Restrictions
 STDOUT is not compatible with Pipes.  The current active page can be determined with the PAGEACTIVE function.

I started this thread because I took them at their word. I can't imagine why the powers that be would break such a basic function without some reason (like a substantial performance gain). I would have assumed STDIN and STDOUT to be as straightforward as cin/cout in C++. I do nothing special to accommodate piping in C++ and Python, yet it always works.

Could I possibly need a .dll that just exports cin and cout for use with PB? BTW, I do have both 4 and 5.

[Michael Mattias]

'CLPIPE.BAS
' test commandline piping
' PBCC 5.0.1
' MCM 4/13/09

#COMPILE EXE
#CONSOLE OFF   ' <<< MAKES NO DIFFERENCE
#DIM ALL

#INCLUDE "WIN32API.INC"

FUNCTION PBMAIN () AS LONG

LOCAL bFirst AS LONG
LOCAL a$

LOCAL hPB AS LONG, hSys AS LONG, L AS LONG


  hSys = GetStdHandle (%STD_INPUT_HANDLE)
  hPB  = FREEFILE
  OPEN HANDLE hSys FOR INPUT AS hPB
  L = LOF(hPB)
  LINE INPUT #hPB, a$
  CLOSE hPB
  hSys = GetStdHandle (%STD_OUTPUT_HANDLE)
  hPB = FREEFILE
  OPEN HANDLE hSys FOR OUTPUT AS hPB
  PRINT #hPB, UCASE$(a$)
  CLOSE hPB


END FUNCTION

D:\Software_Development\pbcc50\Work>echo abcdef |clpipe.exe | more
ABCDEF


D:\Software_Development\pbcc50\Work>echo abcdef |clpipe.exe | more
ABCDEF


D:\Software_Development\pbcc50\Work>

MCM

[Michael Mattias]

Better Still...

'CLPIPE.BAS
' test commandline piping

#COMPILE EXE
#CONSOLE OFF
#DIM ALL

#INCLUDE "WIN32API.INC"

FUNCTION PBMAIN () AS LONG

LOCAL bFirst AS LONG
LOCAL a$

LOCAL hPBI AS LONG, hPBO AS LONG, hSys AS LONG, L AS LONG

  hSys = GetStdHandle (%STD_INPUT_HANDLE)
  hPBI  = FREEFILE
  OPEN HANDLE hSys FOR INPUT AS hPBI
  hSys = GetStdHandle (%STD_OUTPUT_HANDLE)
  hPBO = FREEFILE
  OPEN   HANDLE hSys FOR OUTPUT AS hPBO
  WHILE NOT EOF(hPBI)
     LINE INPUT #hPBI, a$
     PRINT #hPBO, UCASE$(a$)
  WEND
  CLOSE hPBI
  CLOSE hPBO

END FUNCTION

D:\Software_Development\pbcc50\Work>echo abcdef |clpipe.exe | more
ABCDEF


D:\Software_Development\pbcc50\Work>echo abcdef |clpipe.exe | more
ABCDEF


D:\Software_Development\pbcc50\Work>dir *.* | clpipe.exe | more
 VOLUME IN DRIVE D HAS NO LABEL.


D:\Software_Development\pbcc50\Work>dir *.* | clpipe.exe | more


D:\Software_Development\pbcc50\Work>dir *.* | clpipe.exe | more
VOLUME IN DRIVE D HAS NO LABEL.
 VOLUME SERIAL NUMBER IS 049A-2E6F

 DIRECTORY OF D:\SOFTWARE_DEVELOPMENT\PBCC50\WORK

04/13/2009  04:58 PM    <DIR>          .
04/13/2009  04:58 PM    <DIR>          ..
03/19/2009  11:35 AM    <DIR>          ADODEMO
11/10/2008  10:28 AM    <DIR>          BUGS
04/13/2009  04:58 PM               831 CLPIPE.BAK
04/13/2009  04:58 PM               838 CLPIPE.BAS
04/13/2009  04:58 PM            17,920 CLPIPE.EXE
04/13/2009  04:58 PM               610 CLPIPE.LOG
10/27/2008  10:37 AM             1,348 FREESPACE.BAK
10/27/2008  12:02 PM             1,377 FREESPACE.BAS
10/27/2008  10:37 AM            19,456 FREESPACE.EXE
10/27/2008  10:37 AM               621 FREESPACE.LOG
11/20/2008  10:40 AM             1,945 GP001.BAK
11/20/2008  10:40 AM             1,951 GP001.BAS
11/20/2008  10:41 AM            26,112 GP001.EXE
11/20/2008  10:41 AM               654 GP001.LOG
11/20/2008  10:41 AM               165 MEMTEST.BAK
11/20/2008  10:41 AM               153 MEMTEST.BAS
11/20/2008  10:41 AM             6,144 MEMTEST.DLL
11/20/2008  10:41 AM               560 MEMTEST.LOG
01/16/2009  10:54 AM            10,145 NETFINDCOMPUTERS.BAK
01/16/2009  11:04 AM            10,977 NETFINDCOMPUTERS.BAS
01/16/2009  10:54 AM            26,112 NETFINDCOMPUTERS.EXE
01/16/2009  10:54 AM               715 NETFINDCOMPUTERS.LOG
12/02/2008  01:38 PM                56 ORPHAN.TXT
12/02/2008  01:37 PM               653 ORPHANTHREAD.BAK
12/02/2008  01:38 PM               664 ORPHANTHREAD.BAS
12/02/2008  01:38 PM            15,360 ORPHANTHREAD.EXE
12/02/2008  01:38 PM               584 ORPHANTHREAD.LOG
03/20/2009  08:15 AM            27,537 PTMN_LAST_ORDER_NO.BAK
03/20/2009  12:36 PM            27,543 PTMN_LAST_ORDER_NO.BAS
03/20/2009  12:36 PM            76,800 PTMN_LAST_ORDER_NO.EXE
03/20/2009  12:36 PM               764 PTMN_LAST_ORDER_NO.LOG
03/19/2009  05:25 PM             2,203 PTMN_LAST_ORDER_NO_LOG.TXT
03/19/2009  03:42 PM               742 PTMN_LAST_ORDER_NO_LOG.TXT.BAK
10/09/2008  09:13 AM               283 RUNSTDERR.CMD
10/22/2008  09:42 AM             1,982 SHELLEE.BAK
10/22/2008  09:52 AM             1,986 SHELLEE.BAS
10/22/2008  09:52 AM            19,968 SHELLEE.EXE
10/22/2008  09:52 AM               571 SHELLEE.LOG
10/22/2008  09:50 AM             2,711 SHELLER.BAK
10/22/2008  09:52 AM             2,779 SHELLER.BAS
10/22/2008  09:52 AM            17,920 SHELLER.EXE
10/22/2008  09:52 AM               571 SHELLER.LOG
10/09/2008  09:26 AM            10,604 STDERR_BUG.ZIP
01/09/2009  12:57 PM               690 TEST_ARRAYSORT.BAK
01/09/2009  12:59 PM               702 TEST_ARRAYSORT.BAS
01/09/2009  12:59 PM            15,360 TEST_ARRAYSORT.EXE
01/09/2009  12:59 PM               591 TEST_ARRAYSORT.LOG
03/11/2009  11:40 AM               415 TEST_COSINE.BAK
03/11/2009  11:41 AM               415 TEST_COSINE.BAS
03/11/2009  11:43 AM            12,800 TEST_COSINE.EXE
03/11/2009  11:43 AM               580 TEST_COSINE.LOG
10/09/2008  09:21 AM               508 TEST_STDERR.BAK
10/09/2008  09:21 AM               531 TEST_STDERR.BAS
10/09/2008  09:21 AM            17,920 TEST_STDERR.EXE
10/09/2008  09:21 AM               626 TEST_STDERR.LOG
10/09/2008  09:22 AM                14 TEST_STDERR.TXT
10/09/2008  09:22 AM                13 TEST_STDOUT.TXT
10/13/2008  12:36 PM             5,107 TRANSNET1.BAK
10/13/2008  12:47 PM             5,101 TRANSNET1.BAS
10/13/2008  12:36 PM            35,328 TRANSNET1.EXE
10/13/2008  12:36 PM               622 TRANSNET1.LOG
10/13/2008  12:56 PM             1,975 TRANSNET2.BAK
10/13/2008  12:57 PM             2,006 TRANSNET2.BAS
10/13/2008  12:57 PM            29,184 TRANSNET2.EXE
10/13/2008  12:57 PM               622 TRANSNET2.LOG
10/27/2008  10:37 AM                13 ~DS
10/22/2008  09:52 AM               250 ~SHELLTEST.TXT
              65 FILE(S)        472,288 BYTES
               4 DIR(S)  62,216,282,112 BYTES FREE



D:\Software_Development\pbcc50\Work>

Close enough?

MCM

[Michael Mattias]

Even better still (well, better DEMO...)

'CLPIPE.BAS
' test commandline piping
' 4/13/09, 4/15/09 
' PB/CC  5.0.1

#COMPILE EXE
'#CONSOLE OFF  ' <<< does not make any difference if on or off  (if piping in only; required if NOT piping out)
#DIM ALL

#INCLUDE "WIN32API.INC"
FUNCTION PBMAIN () AS LONG

LOCAL bFirst AS LONG
LOCAL a$

LOCAL hPBI AS LONG, hPBO AS LONG, hSys AS LONG, L AS LONG

  hSys = GetStdHandle (%STD_INPUT_HANDLE)
  hPBI  = FREEFILE
  OPEN HANDLE hSys FOR INPUT AS hPBI
  hSys = GetStdHandle (%STD_OUTPUT_HANDLE)
  hPBO = FREEFILE
  OPEN   HANDLE hSys FOR OUTPUT AS hPBO
  WHILE NOT EOF(hPBI)
     LINE INPUT #hPBI, a$
     'PRINT #hPBO, UCASE$(a$)
     PRINT #hPBO, STRREVERSE$(A$)
  WEND
  CLOSE hPBI
  CLOSE hPBO

END FUNCTION

Microsoft Windows XP [Version 5.1.2600]
(C) Copyright 1985-2001 Microsoft Corp.


[B]D:\Software_Development\pbcc50\Work>dir clpipe.* | clpipe.exe[/B]
.lebal on sah D evird ni emuloV
F6E2-A940 si rebmuN laireS emuloV

kroW\05ccbp\tnempoleveD_erawtfoS\:D fo yrotceriD

KAB.epiplc 740,1             MA 81:80  9002/51/40
sab.epiplc 390,1             MA 91:80  9002/51/40
exe.epiplc 029,71            MA 91:80  9002/51/40
gol.epiplc 016               MA 91:80  9002/51/40
setyb 076,02         )s(eliF 4
eerf setyb 886,077,412,26  )s(riD 0


[B]D:\Software_Development\pbcc50\Work>dir clpipe.* | clpipe.exe | clpipe.exe[/B]
Volume in drive D has no label
 Volume Serial Number is 049A-2E6F

 Directory of D:\Software_Development\pbcc50\Work

04/15/2009  08:18 AM             1,047 clpipe.BAK
04/15/2009  08:19 AM             1,093 clpipe.bas
04/15/2009  08:19 AM            17,920 clpipe.exe
04/15/2009  08:19 AM               610 clpipe.log
               4 File(s)         20,670 bytes
               0 Dir(s)  62,214,770,688 bytes free



D:\Software_Development\pbcc50\Work>

[Michael Mattias]

Non-text input, you say? See...

http://www.powerbasic.com/support/pbforums/showpost.php?p=314068&postcount=28

... and that one should work with text or non-text input.

I suppose I should kind of marry up all these examples and put a decent demo into the source code forum, huh?