Commands by prayer (26)

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ssh and attach to a screen in one line.
If you know the benefits of screen, then this might come in handy for you. Instead of ssh'ing into a machine and then running a screen command, this can all be done on one line instead. Just have the person on the machine your ssh'ing into run something like $ screen -S debug Then you would run $ ssh -t [email protected] screen -x debug and be attached to the same screen session.

Lists all clients of a Squid proxy
Generates the list of clients (IPs addresses) that have used the Squid webproxy according to the most recent log. Every IP appears only once in the list.

Connect to SMTP server using STARTTLS
Allows you to connect to an SMTP server over TLS, which is useful for debugging SMTP sessions. (Much like telnet to 25/tcp). Once connected you can manually issue SMTP commands in the clear (e.g. EHLO)

Copy history from one terminal to another
Or just do history -w before opening another terminal.

Find the package that installed a command

Search for files older than 30 days in a directory and list only their names not the full path

launch bash without using any letters
I don't know why anyone would use this, I was just messing around tonight and managed to start bash without using any letters and thought I would share. It's pretty simple, first it tries to execute "-" redirecting stderr to stdout which prints the error "bash: -: command not found" to standard output, then I try to execute "bash: -: command not found" which produces the output "bash: bash: -: command not found: command not found". lastly, (on the other side of the semicolon) I use the underscore environment variable which refers to the last command run ("bash: -: command not found") and take out everything after the first ":" character using brace expressions and your left with "bash"

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

Execute matlab sentences from command line
Execute matlab sentences in shell script: for var in `seq 0 0.2 1` ; do echo "my_function($var);" | matlab -nodisplay done

Show established network connections


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