- Most HTTP servers buffer the output from CGI scripts until the
script is completed. This means that it is not possible to display a
progress report on the client's display while the script is running.
- Check the installation instructions above.
- Check the HTTP server's log files. (
tail -f logfile in a separate
window may be useful!) - Always check a script for syntax errors first, by doing something
like
python script.py. - When using any of the debugging techniques, don't forget to add
import sys to the top of the script. - When invoking external programs, make sure they can be found.
Usually, this means using absolute path names -
$PATH is usually not
set to a very useful value in a CGI script. - When reading or writing external files, make sure they can be read
or written by every user on the system.
- Don't try to give a CGI script a set-uid mode. This doesn't work on
most systems, and is a security liability as well.
guido@CNRI.Reston.Va.US
