Commands by SuperJediWombat (7)

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find the path of the java called from the command line
The output will likely point to '/etc/alternatives/java'. So find out where that points by issuing ls -l like this: ls -l /etc/alternatives/java

List contents of jar
useful to find the list of dependencies

Check (partial) runtime-dependencies of Gentoo ebuilds
The output is only partial because runtime dependencies should count in also commands executed via system() and libraries loaded with dlopen(), but at least it gives an idea of what a package directly links to. Note: this is meaningful *only* if you're using -Wl,--as-needed in your LDFLAGS, otherwise it'll bring you a bunch of false positives.

Multi-line grep
Using perl you can search for patterns spanning several lines, a thing that grep can't do. Append the list of files to above command or pipe a file through it, just as with regular grep. If you add the 's' modifier to the regex, the dot '.' also matches line endings, useful if you don't known how many lines you need are between parts of your pattern. Change '*' to '*?' to make it greedy, that is match only as few characters as possible. See also http://www.commandlinefu.com/commands/view/1764/display-a-block-of-text-with-awk to do a similar thing with awk. Edit: The undef has to be put in a begin-block, or a match in the first line would not be found.

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"

quickly change all .html extensions on files in folder to .htm

Create passwords and store safely with gpg
Adjust the $ head -c part for password length. I use filenames like "hans@commandlinefu.com.gpg" and a vim which automatically decrypts files with .gpg suffixes.

Find the process you are looking for minus the grepped one
Get the PID of a process by name

Start dd and show progress every X seconds

Get AWS temporary credentials ready to export based on a MFA virtual appliance
You might want to secure your AWS operations requiring to use a MFA token. But then to use API or tools, you need to pass credentials generated with a MFA token. This commands asks you for the MFA code and retrieves these credentials using AWS Cli. To print the exports, you can use: `awk '{ print "export AWS_ACCESS_KEY_ID=\"" $1 "\"\n" "export AWS_SECRET_ACCESS_KEY=\"" $2 "\"\n" "export AWS_SESSION_TOKEN=\"" $3 "\"" }'` You must adapt the command line to include: * $MFA_IDis ARN of the virtual MFA or serial number of the physical one * TTL for the credentials


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