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Commands tagged Linux

Commands tagged Linux from sorted by
Terminal - Commands tagged Linux - 187 results
for i in $(pgrep -v -u root);do kill -9 $i;done
2009-03-24 02:54:52
User: lostnhell
Functions: kill
1

explanation:

grep -- displays process ids

-v -- negates the matching, displays all but what is specified in the other options

-u -- specifies the user to display, or in this case negate

The process loops through all PIDs that are found by pgrep, then orders a forced kill to the processes in numerical order, effectively killing the parent processes first including the shells in use which will force the users to logout.

Tested on Slackware Linux 12.2 and Slackware-current

echo 'wget url' | at 01:00
2009-03-21 06:19:40
User: Vlad003
Functions: at echo
15

Replace "url" with the correct address of what your're downloading. Replace 01:00 with what time you want. (24-hour clock).

alias pst='pstree -Alpha'
2009-03-20 10:53:37
User: Alexander
Functions: alias
Tags: Linux
0

By 'pst' you can print out process tree with all details about all processes (including a command line, PID, and the current process you are running in).

By 'pst username' you can get an information about processes belonging to the particular user 'username'.

sed ':a;N;$!ba;s/\n/ /g'
2009-03-17 20:54:04
User: cidiom
Functions: sed
Tags: Linux
0

Ever had a file with a list of numbers you wanted to add, use:

cat file | sed ':a;N;$!ba;s/\n/+/g' | bc
sort file1.txt | uniq > file2.txt
convert image123.png -colors 14 -resize 640x480 grubimg.xpm
2009-03-12 22:55:10
User: starchox
Tags: Linux grub boot
3

* size must be 640?480 pixels

* only has 14 colors

* save it in XPM format

Edit /boot/grub/menu.lst and add

splashimage=(hd0,0)/boot/grub/grubimg.xpm

make sure for your path name and hard disk

find . -print | sed -e 's;[^/]*/;|____;g;s;____|; |;g'
2009-03-12 22:25:26
Functions: find sed
-2

NOT MINE! Taken from hackzine.com blog.

It creates a tree-style output of all the (sub)folders and (sub)files from the current folder and down(deeper)

Quoting some of hackzine's words

"Murphy Mac sent us a link to a handy find/sed command that simulates the DOS tree command that you might be missing on your Mac or Linux box. [..split...] Like most things I've seen sed do, it does quite a bit in a single line of code and is completely impossible to read. Sure it's just a couple of substitutions, but like a jack in the box, it remains a surprise every time I run it."

mv file_name.extension ..
2009-03-09 15:35:58
User: takealeft
Functions: mv
-3

cd into the directory that contains the file.

this is just the usual move command but shortcut'd.

say you wanted to move a photo img1.png from ~/photos/holidayphotos into the parent directory which is ~/photos

command would be:

~/photos/holidayphotos$ mv img1.png ..

I use Ubuntu so this'll work in debian but not sure what else.

INFILE=/path/to/your/backup.img; MOUNTPT=/mnt/foo; PARTITION=1; mount "$INFILE" "$MOUNTPT" -o loop,offset=$[ `/sbin/sfdisk -d "$INFILE" | grep "start=" | head -n $PARTITION | tail -n1 | sed 's/.*start=[ ]*//' | sed 's/,.*//'` * 512 ]
6

Suppose you made a backup of your hard disk with dd:

dd if=/dev/sda of=/mnt/disk/backup.img

This command enables you to mount a partition from inside this image, so you can access your files directly.

Substitute PARTITION=1 with the number of the partition you want to mount (returned from sfdisk -d yourfile.img).

some_cronjobed_script.sh 2>&1 | tee -a output.log | grep -C 1000 ERROR
2009-03-06 17:51:13
User: DEinspanjer
Functions: grep tee
Tags: Linux
-1

The large context number (-C 1000) is a bit of a hack, but in most of my use cases, it makes sure I'll see the whole log output.

taskset -c 0 your_command
2009-02-28 22:38:02
User: Alanceil
Functions: taskset
19

This is useful if you have a program which doesn't work well with multicore CPUs. With taskset you can set its CPU affinity to run on only one core.

for vm in $(vmware-cmd -l);do echo -n "${vm} ";vmware-cmd ${vm} getstate|awk '{print $2 " " $3}';done
2009-02-26 16:45:04
User: dbart
Functions: echo
4

I use this command on my machines running VMware Server to print out the state of all registered Virtual machines.