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Application Examples
Example Program for a CGI Application
WAGO-I/O-SYSTEM
750
Linux Fieldbus Coupler
The function
main_ether()
calls the above-mentioned functions and writes
the HTML code to the standard console stdout. HTML shows the network
configuration in a form. The form has the SUBMIT button
S
AVE
C
ONFIGURATION
which transfers a changed network configuration to the
Linux fieldbus coupler in a QUERY_STRING. You have to enter a user with
root privileges and the corresponding password.
These entries are authenticated in the
crypt.c
file. After successful
authentication, the
S
AVE
C
ONFIGURATION
query string is analyzed and, if a
value is changed, the appropriate
write_...-
function is called.
Source code description:
restart.c
The restart page of the Linux fieldbus coupler is generated in the
restart.c
file.
The file includes the function
main_restart()
main_restart()
writes the HTML code to the standard console stdout.
Furthermore, the query string including the password is analyzed. After
entering a user with root privileges and the corresponding password
(default:user name: root, password: wago) and clicking the
R
EBOOT
button,
reboot
will be called which will reboot the operating system.