I m just starting with C

[groundzero]

I have a question. Im my code how do i tell linux to :
ping hostname and as long is it gets a responce print blablabla>>>
Thanx'
also how can issue a reboot command from user level and not root. Its ok if the are promted for the su password.

[kmj]

I don't have a direct answer for you; but this page will help you with C sockets.
http://www.ecst.csuchico.edu/~beej/guide/net/

[jemfinch]

Really, you should pick a better language to learn, like Python.

To allow a user to reboot, put this in a file and give it execute permissions:

#!/bin/sh
su -c 'shutdown -r now'


Jeremy

[pinoy]

ping involves using a raw socket, so you can format your own icmp packet, and you can also read icmp replies. Not terribly hard, but if you're just starting with C, it may be a while before you get comfortable with it.

[satchel]

You can do a "ping -c 1 $addr"
Then check for the returncode. If its
0(success/host is up) println "blahh"
if its 1(failure/non zero) then do something else. I'm partial to ksh or Perl for this stuff. Something like this in C......?

rc=0
system("ping -c 1 $addr");
if rc
then println "blahhhh"
else
exit

I'm sure this syntax isn't right but this is the basic idea.