Commands by kyle0r (4)

  • In this example, where the users gpg keyring has a password, the user will be interactively prompted for the keyring password. If the keyring has no password, same as above, sans the prompt. Suitable for cron jobs. ~/.gnupg/passwd/http-auth.gpg is the encrypted http auth password, for this particular wget use case. This approach has many use cases. example bash functions: function http_auth_pass() { gpg2 --decrypt ~/.gnupg/passwd/http-auth.gpg 2>/dev/null; } function decrypt_pass() { gpg2 --decrypt ~/.gnupg/passwd/"$1" 2>/dev/null; }


    1
    wget --input-file=~/donwloads.txt --user="$USER" --password="$(gpg2 --decrypt ~/.gnupg/passwd/http-auth.gpg 2>/dev/null)"
    kyle0r · 2012-12-13 00:14:55 7
  • From the cwd, recursively find all rar files, extracting each rar into the directory where it was found, rather than cwd. A nice time saver if you've used wget or similar to mirror something, where each sub dir contains an rar archive. Its likely this can be tuned to work with multi-part archives where all parts use ambiguous .rar extensions but I didn't test this. Perhaps unrar would handle this gracefully anyway?


    10
    find . -name '*.rar' -execdir unrar e {} \;
    kyle0r · 2012-09-27 02:27:03 5
  • the find -printf "%f\n" prints just the file name from the given path. This means directory paths which contain extensions will not be considered. Show Sample Output


    0
    find /some/path -type f -and -printf "%f\n" | egrep -io '\.[^.]*$' | sort | uniq -c | sort -rn
    kyle0r · 2012-04-02 19:25:35 4
  • In this example, the command will recursively find files (-type f) under /some/path, where the path ends in .mp3, case insensitive (-iregex). It will then output a single line of output (-print0), with results terminated by a the null character (octal 000). Suitable for piping to xargs -0. This type of output avoids issues with garbage in paths, like unclosed quotes. The tr command then strips away everything but the null chars, finally piping to wc -c, to get a character count. I have found this very useful, to verify one is getting the right number of before you actually process the results through xargs or similar. Yes, one can issue the find without the -print0 and use wc -l, however if you want to be 1000% sure your find command is giving you the expected number of results, this is a simple way to check. The approach can be made in to a function and then included in .bashrc or similar. e.g. count_chars() { tr -d -c "$1" | wc -c; } In this form it provides a versatile character counter of text streams :) Show Sample Output


    1
    find /some/path -type f -and -iregex '.*\.mp3$' -and -print0 | tr -d -c '\000' |wc -c
    kyle0r · 2012-03-31 21:57:33 5

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umount --rbind mount with submounts
Original: https://bugzilla.redhat.com/show_bug.cgi?id=194342

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"

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.

reverse order of file

Create a mirror of a local folder, on a remote server
Create a exact mirror of the local folder "/root/files", on remote server 'remote_server' using SSH command (listening on port 22) (all files & folders on destination server/folder will be deleted)

Get a range of SVN revisions from svn diff and tar gz them
Handy when you need to create a list of files to be updated when subversion is not available on the remote host. You can take this tar file, and upload and extract it where you need it. Replace M and N with the revisions specific to yours. Make sure you do this from an updated (svn up) working directory.

Notify me when users log in
Notifyme is a program that listen in background for users login, and report on login and logout. Users can be specified from a list or in a ~/notify.rc file. -C options force to display messages on the center of the screen.See man notifyme for more details. Part of notifyme package, tested on Debian.

Simple XML tag extract with sed
Limited, but useful construct to extract text embedded in XML tags. This will only work if bar is all on one line. If nobody posts an alternative for the multiline sed version, I'll figure it out later...

Swap a file or dir with quick resotre
This lets you replace a file or directory and quickly revert if something goes wrong. For example, the current version of a website's files are in public_html. Put a new version of the site in public_html~ and execute the command. The names are swapped. If anything goes wrong, execute it again (up arrow or !!).

watch snapshots commit in VMware ESX
To monitor .vmdk files during snapshot deletion (commit) on ESX only (ESXi doesn't have the watch command): 1. Navigate to the VM directory containing .vmdk files. # watch "ls -tough --full-time *.vmdk" where: -t sorts by modification time -o do not list group information (to narrow the output) -u sorts by access time -g only here for the purpose to easily remember the created mnemonic word 'tough' -h prints sizes in human readable format (e.g., 1K 234M 2G) --full-time sets the time style to full-iso and does not list user information (to narrow the output) optionally useful parameters to the watch command: -d highlight changes between updates -n seconds to wait between updates (default is 2) -t turn off printing the header


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