Commands using grep (1,935)

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Watch the disk fill up with change highlighting
If you add the -d flag each difference in the command's output will be highlighted. I also monitor individual drives by adding them to df. Makes for a nice thin status line that I can shove to the bottom of the monitor.

Quick and dirty convert to flash
This converts any media ffmpeg handles to flash. It would actually convert anything to anything, it's based on the file extension. It doesn't do ANY quality control, sizing, etc, it just does what it thinks is best. I needed an flv for testing, and this spits one out easily.

List all files modified by a command
Often you run a command, but afterwards you're not quite sure what it did. By adding this prefix/suffix around [COMMAND], you can list any files that were modified. . Take a nanosecond timestamp: YYYY-MM-DD HH:MM:SS.NNNNNNNNN $ date "+%F %T.%N" . Find any files that have been modified since that timestamp: $ find . -newermt "$D" . This command currently only searches below the current directory. If you want to look elsewhere change the find parameter, e.g. $ find /var/log . -newermt "$D"

happened to find this not bad software to keep my files and folders safe! Even the free trial version has the fantastic functions to protect any private files from being seen by anyone except me. With it I can encrypt, hide or lock anything I want, amazin
I noticed some spammer posted an advertisement here for "not bad" encryption. Unfortunately, their software only runs under Microsoft Windows and fails to work from the commandline. My shell script improves upon those two aspects, with no loss in security, using the exact same "military-grade" encryption technology, which has the ultra-cool codename "ROT-13". For extra security, I recommend running ROT-13 twice.

Equivalent to ifconfig -a in HPUX

Remove invalid host keys from ~/.ssh/known_hosts
Useful if you have to tunnel ssh through a local port and it complains of the host key being different. Much easier than manually editing the file.

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Poor man's ntpdate

Detect illegal access to kernel space, potentially useful for Meltdown detection
Based on capsule8 agent examples, not rigorously tested

Create a single-use TCP (or UDP) proxy
Redirect the local port 2000 to the remote port 3000. The same but UDP: $ nc -u -l -p 2000 -c "nc -u example.org 3000" It may be used to "convert" TCP client to UDP server (or viceversa): $ nc -l -p 2000 -c "nc -u example.org 3000"


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