Technical data

8. Documentation for Developers
8.6.5. Miscellaneous
This and that (yes, also important!):
• mini_httpd does not protect subdirectories with a password. Each directory must con-
tain a .htaccess file or a link to another .htaccess file.
• KISS - Keep it simple, stupid!
• This information may change at any time without prior notice!
8.6.6. Debugging
To ease debugging of a CGI script you may activate the debugging mode by sourc-
ing the cgi-helper script. Set the variable set_debug to “yes” in order to do
so. This will create a file debug.log which may be loaded down with the URL
http://<fli4l-Host>/admin/debug.log. It contains all calls of the CGI script. The variable
set_debug is not a global one, it has to be set anew for each CGI in question. Example:
set_debug="yes"
. /srv/www/include/cgi-helper
Furthermore, cURL
9
is ideal for troubleshooting, especially if the HTTP headers are not
assembled correctly or the browser displays only blank pages. Also, the caching behavior of
modern Web browser is obstructive when troubleshooting.
Example: Get a dump of the HTTP-Header with ("‘dump"’, -D) and the normal output of
the CGI admin/my.cgi. The “user” (-u) name here shall be “admin”.
curl -D - http://fli4l/admin/my.cgi -u admin
8.7. Boot, Reboot, Dialin And Hangup Under fli4l
8.7.1. Boot Concept
FLI4L 2.0 should offer a clean install on a hard disk or a CompactFlash (TM) media, but also
an installation on a Zip medium or the creation of a bootable CD-ROM should be possible.
In addition, the hard drive version should not be fundamentally different from the one on an
installation disk
10
.
These requirements have been implemented by making it possible to move the files of the
opt.img archive from the previous RAM disk to another medium, be it a partition on a hard
disk or a CF medium. This second volume is mounted to /opt and only symbolic links are
created from there to the rootfs. The resulting layout in the root file system then corresponds
to the one unpacked in the opt directory of the fli4l distribution with one exception – the
files prefix is not applicable. The file opt/etc/rc is then found directly under /etc/rc,
opt/files/bin/busybox under /bin/busybox. It can be ignored that these files may be only
links to a directory mounted read only as long as you do not want to modify them. If you
want to do this, you have to make the files writable before by using mk_writable (see below).
9
see http://de.wikipedia.org/wiki/CURL
10
Originally fli4l could be operated from a single floppy disk. This is no longer supported since it became too
big in file size.
330