Commands using head (314)

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Watch and cat the last file to enter a directory
Great for watching things like Maildir's or any other queue directory.

Display BIOS Information
read the memory from C:0000 to F:FFFF without the need auf dmidecode

list block devices
Shows all block devices in a tree with descruptions of what they are.

Determine if a command is in your $PATH using POSIX
it is generally advised to avoid using which(1) whenever possible. which(1) is usually a csh(1) script, or sometimes a compiled binary. It's output is highly variable from operating system to operating system, so platform independent scripts could become quite complicated with the logic. On HP-UX 10.20, for example, it prints "no bash in /path /path /path ..."; on OpenBSD 4.1, it prints "bash: Command not found."; on Debian (3.1 through 5.0 at least) and SuSE, it prints nothing at all; on Red Hat 5.2, it prints "which: no bash in (/path:/path:...)"; on Red Hat 6.2, it writes the same message, but on standard error instead of standard output; and on Gentoo, it writes something on stderr. And given all these differences, it's still variable based on your shell. This is why POSIX is king. See http://mywiki.wooledge.org/BashFAQ/081 for more ways on avoiding which(1).

List users with running processes
This is different that `who` in that who only cares about logged-in users running shells, this command will show all daemon users and what not; also users logged in remotely via SSH but are running SFTP/SCP only and not a shell.

Send a local file via email
Send it the easy way, with MIME and everything handled for you by an app that knows best.

Calculate md5 sums for every file in a directory tree

Print a row of characters across the terminal
shorter than alternative

Not a kismet replacement...
If you're like some individuals who rely on ndiswrapper and cannot use kismet, this command may be of service. watch -n .5 "iwlist wlan0 scan | egrep 'ESSID|Encryption'" Or... watch -n .5 "iwlist wlan0 scan | egrep 'ESSID|Encryption' | egrep 'linksys'" :-) Hopefully you'll find some dd-wrt compatible routers.

Clean your broken terminal
If something fracks up your terminal, just type in 'reset' and everything should be good again.


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