Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!mailrus!ames!sun-barr!apple!usc!csun!csuna!abcscnuk
From: abcscnuk@csuna.csun.edu (Naoto Kimura)
Newsgroups: comp.binaries.ibm.pc.d
Subject: Re: Looking for a specific utility
Message-ID: <2169@csuna.csun.edu>
Date: 6 Sep 89 19:50:38 GMT
References: <6868@rpi.edu> <20.UUL1.3#5109@pantor.UUCP>
Reply-To: abcscnuk@csuna.csun.edu (Naoto Kimura)
Organization: CSU Northridge
Lines: 109

In article <20.UUL1.3#5109@pantor.UUCP> richard@pantor.UUCP (Richard Sargent) writes:
>
>I have done this regularly from within DOS. Syntax? Try:
>
>c> for %f in (*.*) do your_command_line
>
>Double the % when used in a batch file.
>
>Of course, there are complications if your_command_line creates new files,
>converts *.old to *.new, you can't substitute alternate file name extensions.
>In cases like these, I simply use a "new" directory for the output files.
>
>Example:
>
>c> for %f in (*.old) do sed /this/that/ %f >..\new\%f
>
>
>I hope this helps.
>
>Richard Sargent                   Internet: richard@pantor.UUCP
>Systems Analyst                   UUCP:     uunet!pantor!richard


One problem...  This will fail because DOS will try to open an unnamed
file in the directory ..\new.  Even if it did work, you'd only get the
output of the last sed command.  I discovered this about a year ago when
I wanted to do something similar.  You'll have to write a batch file to
handle such things as redirection.  For example, you want to do the
following:

    FOR %i IN (0 1 2 3 4 5 6 7 8 9) DO Barf < data%i.old > data%i.new

This will not result in what you'd expect.  This will result in
barf trying to read a file called data.new and output the result
to data.old.

You need to create a batch file UGH.BAT in some subdirectory which
contains the following line:

    BARF < %1 > %2

Then you type the following at the command line:

    FOR %i IN (0 1 2 3 4 5 6 7 8 9) DO UGH data%i.old data%i.new

Another warning to those who use batch files -- the output of a batch
file cannot be redirected unless you run a child COMMAND.COM and
redirect its output.  Suppose you had a batch file, for example
BASEBALL.BAT, and you wanted its output to go to a file called OUT.  If
you typed:

    BASEBALL > OUT

you would end up with an empty file OUT, and all the output of
BASEBALL.BAT will go to the screen.   You have to do the following to
get the desired result:

    COMMAND /C BASEBALL > OUT

This problem caused me some headaches for a few hours.  I had a
collection of batch files that created smaller batch files, which then
were in turn either chained to or executed under a child command
processor.  Sometimes the redirection seemed to work, and sometimes it
didn't.  It made a difference where I happened to run the batch files,
as they didn't always use a full pathname to refer to each other.  So
sometimes, the EXE file would be executed, and other times a BAT would
be called :-(

Another thing to remember about running the command processor is NEVER
redirect its input unless you are running a command from it !!!!!   I
did this one day, thinking that it would do the same as if I were on a
UNIX system running bourne shell.   It did what I expected, but
unfortunately, it resulted in the parent COMMAND.COM trying to read
from the input file I specified for the child COMMAND.COM.   I
basically had to reboot the computer.   Of course, I'm sure most of you
have already tried this.

Equally annoying was the fact that even if you redirected the output of
the GWBASIC interpreter, the screen would always be cleared, and the
output would still go to the screen (of course you'd get what you
expected in the file -- the output of the program) !  It seems that the
BASIC interpreters almost completely ignore DOS's stdin and stdout file
handles.  I suppose it makes sense since they seem to ignore everything
else about DOS.

What annoyed me to no end was when I tried to send escape sequences to
the ANSI driver, but couldn't.  I even tried to open a file "CON" and
send my escape sequences to that file, but BASIC just output to the
"CON" device as if I was doing a plain PRINT statement to BASIC's
standard output device.  If you're wondering, I needed to do things like
clear to end of page and clear to end of line, insert line, and delete
line.  I eventually had to get rid of the places where I would've used
insert and delete line, and used a subroutine that output the
appropriate number of spaces to clear to end of page or line.  If
you're wondering why I was doing stuff in BASIC, I was moving a
program on a TRS-80 over to an IBM-PC -- the customer didn't want me to
rewrite the program in some other language because BASIC was all they
could understand :-(.

I used to have similar complaints about Turbo Pascal, but Borland
has fixed the problems with introduction of version 4.0.  At least it
doesn't try to second-guess what you want when you try to open a DOS
device.

                //-n-\\			 Naoto Kimura
        _____---=======---_____		 (abcscnuk@csuna.csun.edu)
    ====____\   /.. ..\   /____====
  //         ---\__O__/---         \\	Enterprise... Surrender or we'll
  \_\                             /_/	send back your *&^$% tribbles !!