Don't ya just love perl? The network was down and I was waiting to work on one of my servers. Friday late, I wanted to go home. So I stamped out this little one line to send a qpage to me when it saw my server. I could go home and relax knowing I'd hear when the network was ready!
Fast Update: I was wondering if 'while' was the best loop for the job. So I tried a 'for' loop and look what I got!

for($?=1;$?>0;`ping penn`){sleep 900}`qpage hck "penn now up"`;
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As I walked out of the office last night that a 'while' loop could do it better with less code.

while(`ping penn`){sleep 900}`qpage hck "penn is up"`;'
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perl -e 'while(1){`ping penn`;if(0==$?){`qpage hck "Penn is up\!"`;exi
+t;}sleep 900;}' &
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perl -e 'for($?=1;$?>0;`ping penn`){sleep 900}`qpage hck "penn now up"
+`;'
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perl -e 'while(`ping penn`){sleep 900}`qpage hck "penn is up"`;'
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