Linux Small Commands (3) Cat

Linux commands (3) Cat

Cat is viewing the contents of a file

?

Command format: Cat file

Common parameter Description:

-N or-nimber the number of rows for all outputs starting from 1.

Example:

cat/etc/passwd

?

-B or-number-nonblank and-n are similar, except that blank lines are not numbered.

Example:

cat/etc/passwd

?

?

-S or-spueeze-blank when you encounter a blank line that has more than two consecutive lines, replace the blank line with one line

?

First go to the home directory, create several files to test, and enter information

#cd ~???????????????? ------Go to the home directory

#touch yy???????????? ------Create a file named yy

#vi yy???????????? ------Edit the file yy, enter 123456789 inside

Press "ESC" key to stop editing, use "shift+:" to pop up the command bar

Input Wq Save

?

There are three major features of cat:

2. #cd ~???????????? ------Go to the home directory

   #cat yy???????? ------Open the file you just created yy

   You can see, print out the information we entered ourselves

   ?

4. Create a file from the keyboard, you can only create a file, you cannot edit an existing file.

   #cd ~???????????? ------Go to the home directory

   #cat > Yy1???????? ------Create the file and enter the content abc,def and use CTRL + C to cancel

   #cat yy1???????? ------using cat to view the newly created YY1

   ?

6. Merge several files into one file

   #cat yy yy1 > Yy2???????? ------Merge and generate a new file

   #cat Yy2???????????????? ------View the new file that you just generated