Commands tagged bash (821)

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Calculate days on which Friday the 13th occurs (inspired from the work of the user justsomeguy)
Friday is the 5th day of the week, monday is the 1st. Output may be affected by locale.

seq (argc=2) for FreeBSD

Equivalent to ifconfig -a in HPUX
Command is properly working on HP-UX 11.31

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

Git diff last two commits
How about this one ?

Recursively Find Images, Convert to JPEGS and Delete
Simple command to convert a large number of images into jpeg-format. Will delete originals after conversion.

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"

Hex math with bc
To do hex to binary: echo 'ibase=16; obase=2; 16*16' | bc # prints: 111100100 To do 16*16 from decimal to hex: echo 'ibase=10; obase=16; 16*16' | bc # prints: 100 You get the idea... Alternatively, run bc in interactive mode (see man page)

Print all commands of a user on commandlinefu.com
This utilizes the Requests and BeautifulSoup libraries in Python to retrieve a user page on commandlinefu, parse it (error-tolerant) and extract all the lines of the following format: gzip * To print them, a list comprehension is used to iterate over the values, and join() is called on a newline character.

Lists all listening ports together with the PID of the associated process
This command is more portable than it's cousin netstat. It works well on all the BSDs, GNU/Linux, AIX and Mac OS X. You won't find lsof by default on Solaris or HPUX by default, but packages exist around the web for installation, if needed, and the command works as shown. This is the most portable command I can find that lists listening ports and their associated pid.


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