Commands by felixhummel (1)

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See a full list of compiler defined symbols
From http://lists.debian.org/debian-devel/2001/01/msg00971.html .

Empty a file

Delete only binary files in a directory
Please note that binary file checking is NOT perfect. So, use it with caution. It does not delete hidden files whose name has a leading '.' character. And it regards an empty file as a binary file.

Clone perms and owner group from one file to another
Copy both perms and owner group from one file to another.

Update your OpenDNS network ip
Intended for dynamic ip OpenDNS users, this command will update your OpenDNS network IP. For getting your IP, you can use one of the many one-liners here on commandlinefu. Example: I use this in a script which is run by kppp after it has successfully connected to my ISP: --- #!/bin/bash IP="`curl -s http://checkip.dyndns.org/ | grep -o '[[:digit:].]\+'`" PW="hex-obfuscated-pw-here" if [ "$IP" == "" ] ; then echo 'Not online.' ; exit 1 else wget -q --user=topsecret --password="`echo $PW | xxd -ps -r`" 'https://updates.opendns.com/nic/update?hostname=myhostname&myip='"$IP" -O - /etc/init.d/ntp-client restart & fi --- PS: DynDNS should use a similar method, if you know the URL, please post a comment. (Something with members.dyndns.org, if I recall correctly)

Convert multiple files using avidemux
Using avidemux to convert multiple files that are in the folder where the command was executed.

Find ASCII files and extract IP addresses

grep for minus (-) sign
Use flag "--" to stop switch parsing

Generate RSA private key and self-signed certificate
This will create, in the current directory, a file called 'pk.pem' containing an unencrypted 2048-bit RSA private key and a file called 'cert.pem' containing a certificate signed by 'pk.pem'. The private key file will have mode 600. !!ATTENTION!! ==> this command will overwrite both files if present.

Replace spaces in filenames with underscorees

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