Path: utzoo!news-server.csri.toronto.edu!cs.utexas.edu!sun-barr!newstop!sun!exodus!wind!naughton
From: naughton@wind.Eng.Sun.COM (Patrick Naughton)
Newsgroups: comp.windows.news
Subject: Re: wanted: pipe operator example
Message-ID: <9202@exodus.Eng.Sun.COM>
Date: 6 Mar 91 17:49:40 GMT
References: <1991Mar5.024148.18582@quorum.com> <755@philica.ica.philips.nl>
Sender: news@exodus.Eng.Sun.COM
Reply-To: naughton@wind.Eng.Sun.COM (Patrick Naughton)
Organization: Sun Microsystems, Inc. - Mountain View, CA
Lines: 51

'readstring' is waiting for exactly 100 characters... (redbook p. 201)

This will work...

(/bin/sh) pipe
/w exch def
/r exch def
w (pwd\n) writestring
w flushfile
r 100 string readline pop ==

also note that you don't need to fork a new /bin/sh, you are already running one as the parent process of NeWS.

So this will work as well...

(pwd) pipe pop 100 string readline pop ==

-Patrick

In article <755@philica.ica.philips.nl>, lex@philica.ica.philips.nl (Lex van Sonderen) writes:
|> I want to use the pipe operator to open a shell, send a command,
|> read the result, send a command, read the result etc...
|> 
|> I do something like this:
|> 
|> /trypipe { % -- -> --
|> 	(/bin/sh) pipe				% readfile writefile
|> 	dup (pwd) writestring			% readfile writefile
|> 	dup flushfile				% readfile writefile
|> 	1 index 100 string readstring {		% readfile writefile str
|> 		==				% readfile writefile
|> 	} {
|> 		pop (nothing\n) ==		% readfile writefile
|> 	} ifelse
|> % now write some more commands
|> % ....
|> 	pop pop					% --
|> } def
|> 
|> Apparently, the operator gets stuck in readstring, no error messages.
|> Closing the writefile before reading the readfile does help, but I
|> want to keep it open.
|> Help!
|> 
|> Lex van Sonderen
|> lex@ica.philips.nl

-- 
    ______________________________________________________________________
    Patrick J. Naughton				   email: naughton@sun.com
    Sun Laboratories				   voice: (415) 336 - 1080