Commands using grep (1,935)

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Watch active calls on an Asterisk PBX
Only the number of calls nothing else.

analyze traffic remotely over ssh w/ wireshark
This captures traffic on a remote machine with tshark, sends the raw pcap data over the ssh link, and displays it in wireshark. Hitting ctrl+C will stop the capture and unfortunately close your wireshark window. This can be worked-around by passing -c # to tshark to only capture a certain # of packets, or redirecting the data through a named pipe rather than piping directly from ssh to wireshark. I recommend filtering as much as you can in the tshark command to conserve bandwidth. tshark can be replaced with tcpdump thusly: $ ssh root@example.com tcpdump -w - 'port !22' | wireshark -k -i -

Hiding and Show files on Mac OS X
These commands will mark a file as hidden or visible to Mac OS X Finder. Notice the capitol V vs the lowercase v. This will also work for directories. setfile -a V foo.bar; // This marks the file invisible setfile -a v foo.bar; // This marks the file visible I have also found that adding the following aliases are helpful: alias hide='setfile -a V' alias show='setfile -a v'

Decrypt passwords from Google Chrome and Chromium.
Read this before you down voting and comment that it is not working -> Wont work on latest versions ~75> since database file is locked and has to be decrypted. This is useful if you have an old hdd with a chrome installation and want to decrypt your old passwords fast.

Identify differences between directories (possibly on different servers)
This can be much faster than downloading one or both trees to a common servers and comparing the files there. After, only those files could be copied down for deeper comparison if needed.

Check SATA link speed.
Check SATA controller type. 6.0 Gbps - SATA III 3.0 Gbps - SATA II 1.5 Gbps - SATA I

grep (or anything else) many files with multiprocessor power
xargs -P N spawns up to N worker processes. -n 40 means each grep command gets up to 40 file names each on the command line.

Get current stable kernel version string from kernel.org
depends on "jq" This is more reliable in my opinion.

Triple monitoring in screen
This command starts screen with 'htop', 'nethogs' and 'iotop' in split-screen. You have to have these three commands (of course) and specify the interface for nethogs - mine is wlan0, I could have acquired the interface from the default route extending the command but this way is simpler. htop is a wonderful top replacement with many interactive commands and configuration options. nethogs is a program which tells which processes are using the most bandwidth. iotop tells which processes are using the most I/O. The command creates a temporary "screenrc" file which it uses for doing the triple-monitoring. You can see several examples of screenrc files here: http://www.softpanorama.org/Utilities/Screen/screenrc_examples.shtml

Advanced python tracing
Trace python statement execution and syscalls invoked during that simultaneously


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