Re: [O] Problems running C code in org-mode under Windows

[Eric Schulte]

Thanks for tracking down the source of this problem.  Unfortunately this
is beyond my abilities to address.  It would be interesting to hear if
others on this list are having issues compiling C code blocks on
windows.  To the extent that this appears to be a problem with the Emacs
`call-process' and the cmdproxy executable maybe a bug report to Emacs
would be appropriate.

Best,

Richard Stanton <address@hidden> writes:

> I've been tracing through, and a problem occurs when the compilation
> gets run, which is at about line 155 in file ob-eval.el, inside
> function org-babel-shell-command-on-region, where call-process region
> is called.
>
> As far as I can see, at this point the command being called is
>
> C:/emacs/emacs-24.0.94/bin/cmdproxy -c "gcc -o 
> \"c:/users/stanton[...]C-bin-10700opx\" 
> \"c:/users/Stanton[...]C-src-10700bfr.c\""
>
> (where [...] just means I deleted some more path information, but it's all 
> valid).
>
> If I execute this exact command at the command line, the compilation
> works fine, and creates an executable file C-bin-10700opx.exe (note
> that gcc on Windows automatically adds the .exe extension if you omit
> it). However, after running the call-process-region command in the .el
> file, no executable file is produced, and error-file has the contents
>
> Access is denied
>
> Not sure why this should be, but the compilation is not happening.
>
>
>
>
>
>> -----Original Message-----
>> From: Eric Schulte [mailto:address@hidden
>> Sent: Monday, March 26, 2012 6:45 PM
>> To: Richard Stanton
>> Cc: address@hidden
>> Subject: Re: [O] Problems running C code in org-mode under Windows
>> 
>> Richard Stanton <address@hidden> writes:
>> 
>> > Here's a simple org file that's supposed to run some C code and print the
>> result:
>> >
>> > ----------------------
>> >
>> > * Sample C code
>> >
>> > #+name: RHS.c
>> > #+begin_src C :noweb yes :tangle RHS.c
>> >   #include <stdio.h>
>> >   <<main>>
>> > #+end_src
>> >
>> > #+name: main
>> > #+begin_src C
>> >   int main(int argc, char *argv[]) {
>> >     int lst[argc-1];
>> >     int i;
>> >     for(i=1;i<argc;i++)
>> >       lst[i-1] = atoi(argv[i]);
>> >     for(i=1;i<argc;i++)
>> >       printf("%d ", lst[i-1] + 1);
>> >     printf("\n");
>> > }
>> > #+end_src
>> >
>> > #+call: RHS.c[:cmdline 8 7 6]()
>> >
>> > -------------------------
>> >
>> > It works fine on my Mac, producing the result:
>> >
>> > #+RESULTS: RHS.c[:cmdline 8 7 6]()
>> > : 9 8 7
>> >
>> > On my PC, however, running Windows Vista, the output is blank and
>> > there's a *Org-babel-error-output* buffer containing the message
>> >
>> > Access is denied.
>> > 'c:/Users/stanton/AppData/Local/Temp/babel-11948MQP/C-bin-11948Nln'
>> is
>> > not recognized as an internal or external command, operable program or
>> > batch file.
>> >
>> > There is a file called C-bin-11948Nln in that directory, but it has
>> > length 0, suggesting that something is going wrong in the compilation
>> > process. However, I can also see potential problems with the fact that
>> > the file name does not end in .exe, so the Windows shell is not easily
>> > going to recognize it as an executable anyway.
>> >
>> > Does anyone have this running OK under Windows? Alternatively, how can
>> > I track down what's going wrong in more detail?
>> >
>> > Thanks.
>> >
>> > Richard Stanton
>> >
>> 
>> I don't have access to a windows machine so I can't debug this myself, but I
>> would suggest stepping through the execution of the `org-babel-C-execute'
>> function using edebug.  This is done by first placing the cursor inside the 
>> `org-
>> babel-C-execute' function, evaluating the function with C-u C-M-x, then
>> executing a C code block.  This should give you some idea of what is going
>> wrong where.
>> 
>> Best,
>> 
>> --
>> Eric Schulte
>> http://cs.unm.edu/~eschulte/

-- 
Eric Schulte
http://cs.unm.edu/~eschulte/