Linux Basic Text View command (cat,tac,rev,head,tail,more,less)

Linux we always have to view the text of certain content, if we only because the view text to use VI into the file and added a lot of extra operation inconvenient. Here are some text-viewing commands that you should look after to help

Cat

cat-concatenate files and print on the standard output

Expression format:cat [OPTION] ... [FILE] ...

Common options:

-A: Show all control characters

-N: Displays the number of rows

-E: Display line terminator

Here are a few examples to illustrate the use of cat and its options

Experimental catalogue/test Text/TEST/CAT1/TEST/CAT2

[[email protected] test]# ll /test/total dosage  8- Rw-r--r--.  1 root root 43 8 Month    7 16:46 cat1-rw-r--r--.   1 root root 19 8 Month    7 16:46 cat2[[email protected] test ]# cat cat1    hi,everyonenow i will show how to  Use cat[[email protected] test]# cat -an cat1     1   hi,everyone$     2  now i will show how  to use cat$[[email protected] test]# cat -nE cat1 cat2      1  hi,everyone$     2  now I  Will show how to use cat$     3  this is  an example$ 

Cat can be followed by multiple files, common options can be combined with

TAC reverse display of cat, reversed by text

Tac-concatenate and print files in reverse

TAC [OPTION] ... [FILE] ...

[[Email protected] test]# TAC Cat1now I'll show how to use Cathi,everyone

TAC options are not commonly used and are therefore not introduced

Rev The contents of the file are displayed in reverse order.

Rev-reverse lines of a file or files

Rev [options] [file ...]

[Email protected] test]# rev cat1 Enoyreve,ihtac esu ot woh wohs lliw I won

Rev has no value to introduce options

Head

Head-output the first part of the files

Head [OPTION] ... [FILE] ...

Common options:

-C #: Shows the number of bytes before

-N #: Shows the number of rows before n can save

The first 10 lines of the file are displayed by the head file

[[email protected] test]# head-3 head 123456789012[[email protected] test]# head-c 3 head 123[[email protected] test]#

Tail

Tail-output the last part of the files

Tail [OPTION] ... [FILE] ...

Common options:

-C #: Number of bytes after display

-N #: Shows how many lines, N can save

-F: Trace display File New additions, common log monitoring

[[email protected] test]# tail-3 head 3451236[[email protected] test]# tail-c 5 head 236[[email protected] test]# tail -f/var/log/messagesaug 7 17:15:04 localhost dhclient[9668]: DHCPDISCOVER on eno16777728 to 255.255.255.255 port Inter Val One (xid=0x7773726a) 7 17:15:05 localhost networkmanager[916]: <warn> (eno16777728): DHCPv4 Request timed OU T.aug 7 17:15:05 localhost networkmanager[916]: <info> (eno16777728): DHCPV4 state changed unknown-timeout. .

More features: Automatic exit after turning the screen to the tail of the file

More-file perusal filter for CRT viewing

Expression format: More[options] file [...]

[[email protected] ~]# man /etc/init.d/functions...                 ;;            stop)                     s=$ "Stopping$prog  (via  SYSTEMCTL):  "                   ;;           reload|try‐reload)                    s=$ "Reloading   $prog   configuration  (VIASYSTEMCTL):  "                  ;;          restart|try‐restart|con‐drestart)                   s=$ "Restarting  $prog   ( VIA SYSTEMCTL):  "                 ;;          esac manual page functions line  1  (Press h for help or q to quit)

Less

Less-opposite of more

In less, you can use the previous search function in man, and you can simply assume that less is a more enhanced version.

Less turns the screen to the end of the file and does not exit automatically.

[Email protected] ~]# less/etc/init.d/functions

This article is from "Zhang Fan-it's fantasy drifting" blog, please be sure to keep this source http://chawan.blog.51cto.com/9179874/1835392

Linux Basic Text View command (cat,tac,rev,head,tail,more,less)