Multi-variable CGI

zgauthier · 11-21-2004, 12:31 PM

I've been slaving over google for what seem like days now and have yet to find a way to pass multiple variables to a cgi script. What I've got set up so far is an html document that has two forms on it. The user enters things into the forms and clicks submit. It then sends these variables to my cgi script. At this point this is what I have.

HTML Frontend

Code:

<HTML>


<FORM METHOD=get

ACTION="/cgi-bin/new.cgi">

<input type=string name=input>

<input type=string name="input1">

<input type=submit value="Submit">

</form>

</HTML>

CGI Script

Code:

#!/bin/bash

echo "Content-type: text/html"

echo ""

echo "<HTML>"

  host="`echo $QUERY_STRING | awk -F= '{print $2}'`"

  junk="`echo $host | awk -F& '{print $1}'`"

  test="`echo $QUERY_STRING | awk -F= '{print $3}'`"

  echo "<blockquote><PRE>"

  echo "$junk is to $test"

  echo "</pre></blockquote>"


echo "</HTML>"

exit 0

I think this would work if I could get awk to use & as a seperator, but I've only had success with = for some reason. Right now that code generates " is to dog" if cat and dog are entered into each input box.

david_ross · 11-21-2004, 01:40 PM

Try this - remember to use <body> tags and that the type is text not string:

Code:

<html>
 <body>
  <form method="GET" action="/cgi-bin/new.cgi">
   <input type="text" name="input">
   <input type="text" name="input1">
   <input type="submit" value="Submit">
  </form>
 </body>
</html>

This code should work for the backend:

Code:

#!/bin/bash

echo -e "Content-type: text/html\n\n<html><body>"

IFS="&"
for pair in $QUERY_STRING;do
 name=`echo $pair | awk -F= '{print $1}'`
 value=`echo $pair | awk -F= '{print $2}'`
 echo "$name is $value<br>"
done

echo "</body></html>"

exit 0

zgauthier · 11-21-2004, 01:43 PM

Thanks a lot man. I did come up with a solution shortly after posting this. However it's not nearly as clean as yours.

This is what I came up with.

Code:

#!/bin/bash

echo "Content-type: text/html"

echo ""

echo "<HTML>"

#These lines love each other...

  junk="`echo $QUERY_STRING | awk -F= '{print $2}'`"

  var="`echo $junk | awk -F'&' '{print $1}'`"

#End of line love

  var1="`echo $QUERY_STRING | awk -F= '{print $3}'`"

  echo "<blockquote><PRE>"

  echo "$var is to $var1"

  echo "</pre></blockquote>"


echo "</HTML>"

zgauthier · 11-21-2004, 02:25 PM

OK I thought this would work out great, but now it's driving me insane.

I'm setting up my box so people can give 3 inputs, frequency, duration, and receptions. I'm trying to write a script that will pass that data to the beep program that beeps my motherboard speaker. I had this working fine when it only took one variable. Something here is messed up. When the html frontend calls this page http://z4x.net:81/cgi-bin/private/se...epetitions=334 I get this for an output "2500 500 334 2500 500 334 2500 500 334". Now, why in the world is it repeating 3 times?

This is my adaptation of your example script.

Code:

#!/bin/bash

echo -e "Content-type: text/html\n\n<html><body>"

IFS="&"
for pair in $QUERY_STRING;do
 hz=`echo $pair | awk -F= '{print $2}'`
 echo "$hz"
done

for pair in $QUERY_STRING;do
 ms=`echo $pair | awk -F= '{print $2}'`
 echo "$ms"
done

for pair in $QUERY_STRING;do
 reps=`echo $pair | awk -F= '{print $2}'`
 echo "$reps"
done


echo "</body></html>"


exit 0

david_ross · 11-21-2004, 02:33 PM

Because you have 3 for loops. Just use the one for loop like my example and test for what $name is to find out what veriable you are on.

zgauthier · 11-21-2004, 03:56 PM

OK this is pissing me off, can we say that here? I can get it to spit out all the names, or all the values, but no matter what I try, I can't get it to just give me one value. Even awking $value for $1 is all messed up. I need it to assign each individual value as a variable, not all 3 as one. It seems what you gave me would work if there was only one pair of values in the query string, but I need to use more than that.

david_ross · 11-23-2004, 12:56 PM

You can pick out the variable you want by testing $name in an if statement for the name you want.