Commands by RAKK (5)

  • Lists directory size up to a maximum traversal depth on systems like IBM AIX, where the du command doesn't have Linux's --max-depth option. AIX's du uses -g to display directory size on gigabytes, -m to use megabytes, and -k to use kilobytes. tr### is a Perl function that replaces characters and returns the amount of changed characters, so in this case it will return how many slashes there were in the full path name. Show Sample Output


    0
    du -g | perl -ne 'print if (tr#/#/# == <maximum depth>)'
    RAKK · 2014-02-15 07:33:36 0
  • This command allows you to mirror folders or files with rsync using a secure SSH channel with a forced HMAC integrity algorithm. Use this if you are absolutely adamant about preserving data integrity while mirroring a set of files. --partial is for resumability.


    0
    rsync -av -e "ssh -o MACs=hmac-ripemd160" --progress --partial [email protected]://path/to/remote/stuff .
    RAKK · 2014-02-01 00:46:38 0
  • This command is used to verify a sha256sum-formatted file hash list on IBM AIX or any other UNIX-like OS that has openssl but doesn't have sha256sum by default. Steps: 1: Save to the filesystem a script that: A: Receives as arguments the two parts of one line of a sha256sum listing B: Feeds a file into openssl on SHA256 standard input hash calculation mode, and saves the result C: Compares the calculated hash against the one received as argument D: Outputs the result in a sha256sum-like format 2: Make the script runnable 3: Feed the sha256sum listing to xargs, running the aforementioned script and passing 2 arguments at a time Show Sample Output


    0
    echo '#! /usr/bin/ksh\ncat $2 | openssl dgst -sha256 | read hashish; if [[ $hashish = $1 ]]; then echo $2: OK; else echo $2: FAILED; fi;' > shacheck; chmod +x shacheck; cat hashishes.sha256 | xargs -n 2 ./shacheck;
    RAKK · 2013-09-18 21:51:20 2
  • This command is for UNIX OSes that have plain vanilla System V UNIX commands instead of their more functional GNU counterparts, such as IBM AIX.


    1
    gzip -cd gzippedarchive.tar.gz | tar -xf -
    RAKK · 2013-09-18 17:41:25 0
  • This command is for producing GNU sha256sum-compatible hashes on UNIX systems that don't have sha256sum but do have OpenSSL, such as stock IBM AIX. 1.- Saves a wrapper script for UNIX find that does the following: A.- Feeds a file to openssl on SHA256 hash calculation mode B.- Echoes the output followed by the filename 2.- Makes the file executable 3.- Runs find on a directory, only processing files, and running on each one the wrapper script that calculates SHA256 hashes Pending is figuring out how to verify a sha256sum file on a similar environment. Show Sample Output


    0
    echo '#! /usr/bin/ksh\necho `cat $1 | openssl dgst -sha256` $1' > sslsha256; chmod +x sslsha256; find directory -type f -exec ./sslsha256 \{\} \;
    RAKK · 2013-09-18 17:37:50 0

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Delete all non-printing characters from a file
tr has some predefined sets of characters that are more convenient to use than characters codes

Indent a one-liner.
I often write a one-liner which I want to use later in a script.

File rotation without rename command
Rotates log files with "gz"-extension in a directory for 7 days and enumerates the number in file name. i.e.: logfile.1.gz > logfile.2.gz I needed this line due to the limitations on AIX Unix systems which do not ship with the rename command.

Colored SVN diff
Simple way to achieve a colored SVN diff

Show directories in the PATH, one per line
This version uses Pipes, but is easier for the common user to grasp... instead of using sed or some other more complicated method, it uses the tr command

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

Join lines
Even shorter. Stolen from comment posted by eightmillion.

A function to find the newest file in a directory

Rename files in batch

check open ports without netstat or lsof


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