Linux programming file Operations Linux Knowledge Learning

Linux file content Viewis aLinuxOperations , the following is an essentialLinuxview a summary of the commands under common file content.

1. Cat starts displaying the contents of the file from the first line

Usage:

Cat-a is equivalent to-vet 's integration options, which can list some special characters rather than blanks;

Cat-b List line number, only for non-blank lines to do line number display, blank line is not marked line number;

Cat-e The end of the break-break byte $ display;

Cat-n printed travel numbers, along with blank lines, will have line numbers, unlike the-B option;

Cat-t the [tab] button to display ^i;

Cat-v lists some special characters that cannot be seen;

2. The TAC starts displaying the contents of the file from the last line

Tac-b Add a separator mark before the line and not at the end;

Tac-r The separation mark as a regular expression to parse;

Tac-s uses the specified string instead of line break as the separator flag;

3. NL display line number

Nl-b a travel number, whether or not it is a blank line;

Nl-b T blank line does not list line numbers;

Nl-n LN line number is displayed on the left of the screen ;

The Nl-n RN line number is displayed on the very right of its own field and does not add 0;

Nl-n RZ line number in its own field on the right of the display, and add 0;

Nl-w the number of digits occupied by the row number field;

4. more page-by-page display file contents

while the more program is running, you can press the following key:

Blank Key (space) : Represents a page down;

Enter: Represents a downward turn "line";

/ string: Represents the keyword in this display, down search for "string";

: F: Immediately display the file name and the number of lines currently displayed;

Q: The delegate immediately leaves more and no longer displays the contents of the file.

b or [Ctrl]-b: Represents a page back, but this action is only useful for files and useless for pipelines.

5. Less is similar to more, but better than more , he can page forward

The commands you can enter at run time are:

Blank key: Flip one Page down;

[PageDown] : Flip one page down;

[PageUp] : Flip one page up;

/ string: Search down the function of "string";

? string: Search up the function of "string";

N: Repeat the previous search ( with / or ?) about! ) ;

N: Reverse the repetition of the previous search ( and / or ?) about! ) ;

Q: Leave less this program;

6. Head shows the first few lines

Grammar:

Head-n followed by numbers, representing the number of rows displayed;

7. Tail show the following lines

Tail-n followed by numbers, representing the number of rows displayed;

Tail-f means continuous detection of the following file name, to wait until the [ctrl]-c will end tail detection;

the above is a more commonly used Linux file Content view command , this article only makes the simple grammar introduction, the concrete usage, but also needs to look for the study!

Linux programming file Operations Linux Knowledge Learning