Commands using grep (1,935)

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find an unused unprivileged TCP port
perl-less way

get colorful side-by-side diffs of files in svn with vim
This will diff your local version of the file with the latest version in svn. I put this in a shell function like so: $svd() { vimdiff

Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

Count Files in a Directory with Wildcards.
Remove the '-maxdepth 1' option if you want to count in directories as well

Reverse SSH
this command from the source server and this follow in the destination server: ssh user@localhost -p 8888

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

Test load balancers
With the "--resolve" switch, you can avoid doing DNS lookups or edit the /etc/hosts file, by providing the IP address for a domain directly. Useful if you have many servers with different IP addresses behind a load balancer. Of course, you would loop it: $ for IP in 10.11.0.{1..10}; do curl --resolve subdomain.example.com:80:$IP subdomain.example.com -I -s; done

Script executes itself on another host with one ssh command
Now put more interesting stuff on the script in replacement of hostname, even entire functions, etc, and stuff. hosta> cat myScript.sh #!/bin/sh [ $1 == "client" ] && hostname || cat $0 | ssh $1 /bin/sh -s client hosta> myScript.sh hostb hostb hosta>

Lists the size of certain file in every 10 seconds
watch is a command especially designed for doing this job

rename all images in folder with prefix of date and time from exif data
imagemagick is required


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