[plt-scheme] Mac OS X 10.1.5, Apache 1.3.26, MZScheme 201 and CGI/Shell Scripting

From: Scott Rogers (scott at scottrogers.org)
Date: Fri Oct 11 15:16:08 EDT 2002


I am running the following configuration:
Mac OS X 10.1.5
Apache 1.3.26
MZScheme 201

And I am working on a CGI application.  Here is the problem, when I 
execute the script from the command line, I get the expected result.  
When I execute it as a CGI from Apache,  get #<eof> returned.  I am able 
to run mzscheme CGI scripts, but this on causes me a problem.

When the shell script is executed from the command line like so:

The following is appears on stdout:
Content-type: text/html

However, when I execute it as a CGI through Apache, the following is 
returned to the browser:

;;; Scheme Script

":";exec /usr/local/bin/mzscheme -r $0 "$@"

(require (lib "cgi.ss" "net"))
(require (lib "process.ss"))


(define get-last-topic-id
   (lambda ()
     (let ((p "/Users/scottr/projects/discuss/bin/gltid.sh")
	  (a "/Users/scottr/projects/discuss/data/topics.current"))
       (cond ((not (file-exists? p))
	     (display p)
	     (display ": does not exist.<br/>"))
	    ((not (file-exists? a))
	     (display a)
	     (display ": does not exist.<br/>"))
	    ( #t
	      (display p)(display "<br/>\n")
	      (display a)(display "<br/>\n")
	      (let ((results (process* p a)))
		(let ((topic-id  (read-line (car results))))
		  (close-input-port (car results))
		  (close-output-port (cadr results))
		  (close-input-port (cadddr results))
		  (if (eof-object? topic-id)

(display (get-last-topic-id))
(display "\n")

;;; The shell script it's calling is as follows:
sort -n -t , -k 1 $1 | awk -F, -f $HOME/projects/discuss/bin/gltid.awk

;;; The awk script is as follows:
# Get Last Topic ID
BEGIN { FS = ","; }
   id =  $1;
END { print( id ); }

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