Steel Bank Common Lisp

Friedrich Dominicus <frido@...> writes:

> /bin/cat: /tmp/t1.txt | /bin/grep eins: No such file or directory
>
> what am I doing wrong?

RUN-PROGRAM is a wrapper around fork()/exec(); it does not touch the
shell.  The pipe character | is a shell feature which arranges for a
pipe to connect the output of one process to the input of the other.

> What I want in the end is that I run an external program, maybe in a
> piple which should give me a stream from which I can read. How am I
> supposed to do that in SBCL?

Construct your pipes, either using SB-POSIX or by running two programs
with run-program and connecting the streams up yourself (but beware:
possible deadlocks lurk).

Cheers,

Christophe

Christophe Rhodes writes:
 > Friedrich Dominicus <frido@...> writes:
 > 
 > > /bin/cat: /tmp/t1.txt | /bin/grep eins: No such file or directory
 > >
 > > what am I doing wrong?
 > 
 > RUN-PROGRAM is a wrapper around fork()/exec(); it does not touch the
 > shell.  The pipe character | is a shell feature which arranges for a
 > pipe to connect the output of one process to the input of the other.
 > 
 > > What I want in the end is that I run an external program, maybe in a
 > > piple which should give me a stream from which I can read. How am I
 > > supposed to do that in SBCL?
 > 
 > Construct your pipes, either using SB-POSIX or by running two programs
 > with run-program and connecting the streams up yourself (but beware:
 > possible deadlocks lurk).

        Or by constructing a valid shell pipeline, and call it via "sh
-c".

        Example:

(with-open-file (stream "test.out" :direction :output
                        :if-does-not-exist :create :if-exists :supersede)
  (sb-ext:run-program "/bin/sh" (list "-c" 
                                 "/bin/cat /tmp/t1.txt | /usr/bin/grep eins")
                      :input t :output stream :wait nil))

-- 
Raymond Wiker                        Mail:  Raymond.Wiker@...
Senior Software Engineer             Web:   http://www.fast.no/
Fast Search & Transfer ASA           Phone: +47 23 01 11 60
P.O. Box 1677 Vika                   Fax:   +47 35 54 87 99
NO-0120 Oslo, NORWAY                 Mob:   +47 48 01 11 60

I've run into a problem using sb-ext:run-program that probably has 
something to do with environment setup but has me stumped.
Yet, from an xterm I can type this command:

ssh rh@... 'DISPLAY=:0 srot capture.png'

And it works fine.

But When I try this from the REPL I get:

(sb-ext:run-program "ssh" '("rh@..." "'DISPLAY=:0 scrot 
capture.png'")
                     :output *standard-output* :search t :wait t)

bash: DISPLAY=:0 scrot capture.png: command not found
#<SB-IMPL::PROCESS :EXITED 127>

And yet, this works as expected:

(sb-ext:run-program "ssh" '("rh@..." "'ls'") :output 
*standard-output* :search t :wait t)

Desktop
capture.png
cron.log

Any ideas what's going on and how to make it work? I've tried a few 
things with the :environment parameter w/o success.

Best regards,
Jeff Cunningham

On 29 January 2013 04:05, Jeff Cunningham <jeffrey@...> wrote:

> I've run into a problem using sb-ext:run-program that probably has
> something to do with environment setup but has me stumped.
> Yet, from an xterm I can type this command:
>
> ssh rh@... 'DISPLAY=:0 srot capture.png'

Tracing the exec for this might be interesting.

>
> And it works fine.
>
> But When I try this from the REPL I get:
>
> (sb-ext:run-program "ssh" '("rh@..." "'DISPLAY=:0 scrot
> capture.png'")
>                      :output *standard-output* :search t :wait t)

Try:

(sb-ext:run-program "ssh" '("rh@..." "DISPLAY=:0 scrot capture.png")

                    :output *standard-output* :search t :wait t)

Yours was equivalent to:

  ssh rh@... "'DISPLAY=:0 srot capture.png'"

Ie. you want ssh to get a single string as the second argument -- not
a quoted single string.

Cheers,

 -- Nikodemus

On 29 January 2013 04:05, Jeff Cunningham <jeffrey@...> wrote:
>> ssh rh@... 'DISPLAY=:0 srot capture.png'
>> [...]
>> (sb-ext:run-program "ssh" '("rh@..."
>>                             "'DISPLAY=:0 scrot capture.png'")
>>                      :output *standard-output* :search t :wait t)

* Nikodemus Siivola <nikodemus@...> [2013-01-29 08:17]:
> Try:
> (sb-ext:run-program "ssh" '("rh@..."
>                             "DISPLAY=:0 scrot capture.png")
>                     :output *standard-output* :search t :wait t)

Also, s/scrot/srot/.

'srot' was a typo. The command was supposed to be 'scrot'. Screen 
capture program.


On 01/29/2013 02:47 AM, Will Mengarini wrote:
> On 29 January 2013 04:05, Jeff Cunningham <jeffrey@...> wrote:
>>> ssh rh@... 'DISPLAY=:0 srot capture.png'
>>> [...]
>>> (sb-ext:run-program "ssh" '("rh@..."
>>>                              "'DISPLAY=:0 scrot capture.png'")
>>>                       :output *standard-output* :search t :wait t)
> * Nikodemus Siivola <nikodemus@...> [2013-01-29 08:17]:
>> Try:
>> (sb-ext:run-program "ssh" '("rh@..."
>>                              "DISPLAY=:0 scrot capture.png")
>>                      :output *standard-output* :search t :wait t)
> Also, s/scrot/srot/.