The Linux shell command gets the MD5 value of the string/file

Gets the MD5 value of the string:

MD5 of the string "Hello":

$ Echo-n ' Hello ' |md5sum|cut-d '-f1

The resulting MD5 value:

5d41402abc4b2a76b9719d911017c592

Command explanation:

Md5sum: displays or checks the MD5 (128 bit) checksum. If there is no file option, or the file is "-", it is read from the standard input.
Echo - N: do not print line breaks.
Cut: cut is used to cut columns or fields from standard input or text files. Cut text to paste it into a text file.
-D specifies a different field separator from the space and tab keys. -F1 represents the first field. Refer here.

Gets the MD5 value of the file:

$ md5sum linuxmint-12-gnome-dvd-32bit.iso|cut-d "-f1

The resulting MD5 value:

Ee3d6e2ca498bc7685b7f17cdb5f2eea

Use MD5 to verify the ISO file:

$ md5sum Linuxmint-12-gnome-dvd-32bit.iso >linuxmint-12-gnome-dvd-32bit.md5

Note the contents of the LINUXMINT-12-GNOME-DVD-32BIT.MD5 are:

Ef3d6e2ca498bc7685b7f17cdb5f2eea Linuxmint-12-gnome-dvd-32bit.iso

Put Linuxmint-12-gnome-dvd-32bit and its verification files

LINUXMINT-12-GNOME-DVD-32BIT.MD5 put the following command in the same directory:

$ md5sum-c LINUXMINT-12-GNOME-DVD-32BIT.MD5

Output if the checksum is correct:

Linuxmint-12-gnome-dvd-32bit.iso: OK

If the checksum error is output:

Linuxmint-12-gnome-dvd-32bit.iso: failed
Md5sum: warning: 1 / 1 generated checksum mismatch
Command interpretation:
MD5 - C: read and check the check value of MD5 from the file 

Message Digest algorithm MD5 is a hash function widely used in the field of computer security to provide integrity protection for messages. The algorithm's file number is RFC 1321 (R.rivest,mit Laboratory for computer science and RSA Data Security Inc. April 1992)

Keywords:hash,sha,ronald L. RIVEST,MD5,IETF (Internet Engineering Task Force)

This article from "Nicol Lock Silk Sorrow" blog, please make sure to keep this source http://smoke520.blog.51cto.com/9256117/1917014

The Linux shell command gets the MD5 value of the string/file