All commands

xargs is a more elegant approach to executing a command on find results then -exec as -exec is meant as a filtering flag.

calculate how many different lines between two files

outputs a history of logins on the server (top 10, when piped to 'head'); optional flags: '-a' put the hostname at the end of the line (good for long hostnames), '-i' post the IP instead of the hostname, '-F' put the full login and logout times, rather than short times.

Throttle download speed

Throttle upload speed

Axel

--max-speed=x, -s x

You can specify a speed (bytes per second) here and Axel will

try to keep the average speed around this speed. Useful if you

don?t want the program to suck up all of your bandwidth.

This line unbuffers the interactive output of rsync's --progress flag

creating a new line for every update.

This output can now be used within a script to make actions (or possibly piped into a GUI generator for a progress bar)

Sometime you need to monitor file or direcory change in dimension or other attributes. This command output file (called myfile in the example) attributes in the top of the screen, updating each 1 second.

You should change update time, command ( e.g., ls -all ) or target ( myfile, mydir, etc...).

Creates a PDF from multiple images. One page per image.

If you want a specific arbitrary order you can use {1,3,5,10,12}

* you may use jpg, tif etc

** if you do use jpg images you might want to add "-compress Zip" as suggested below to prevent from having the images from being re-compressed.

Requires mencoder.

Usefull if you only want to see the package names, or if you want to use them in a script.

vim can open ssh/sftp and ftp connections for file editing using 'netrw'. If no path or file is provided vim opens the directory as a filelist.

See: :help netrw.

zsh globbing and glob qualifier:

'**/*' = recursive

om = ouput by modification (last access)

[1,20] = twenty files.

The '-t' switch is provided to ls so that the files are ordered with the most recent at the top. For a more 'find' like output the following can be used.

print -rl **/*(om[1,20])

example of the use of zsh glob qualifiers:

"@" = the symlink qualifier

"[1]" = first element

:t = remove leading path components, leaving the tail

perfect on a crashed system where you can't use commands like last. for investigation purposes wtmp file can be copied over to a different server and read with utmpdump

A method for aquiring the ip address using zsh. If you prefer the use of iproute2 (which, frankly, you should) then the following should provide the same (ip outputs CIDR addresses):

print ${$(ip -o -4 a s eth0)[4]}

we could also pass a qualifier to take only the IP and not the (CIDR) mask

print ${$(ip -o -4 a s eth0)[4]:h}

or, similarly, for the MAC address:

print ${$(ip l l eth0)[15]}

Reason can be: taken, available, contains_banned_word

zsh:

"**/*" = recursive

"(.Lm+100)" "." = files, "L" = filesize glob qualifier, "m" = mb, "+100" = 100

I use these command to validate twitter accounts, we can use a "for a in $(cat list.txt)" to validate a complete list of twitter accounts.

example of zsh globbing and glob qualifiers:

"**/*" recursive

(.m0) '.' = regular file, 'm0' = modified zero days (so, today).