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How to make a new file in linux update#

Note: To save and exit from the vi text editor, press the Escape key and then type :wq and hit enter. Major operations that can be done using it are as follows: It is commonly used by programmers to edit the textual content of any file on vi text editor. Modify time is the time when a file was modified. We can see the access, modify, and change is now updated.Īccess time is the last time when the file was accessed. Note: We are using stat file_name to check the timestamp of the file. To change the timestamp of the file stat filea Note: Creating a file and then using the cat command to view the data.

How to make a new file in linux update#

But its main purpose is to change or update the time-stamp of a file. We can create an empty file (or multiple empty files) using this command. To reverse the data of the file (tac) tac file1 If any file with file name file2 exists in the current directory then it is overwritten with the contents of file1. This command creates a new file file2 with the contents of file1 if file2 doesn’t exist in the present working directory. To copy the file’s data (the content of one file into another) cat file1 > file2 If any file with file name file2 exists in the current directory then it is opened (in append mode). This command creates a new file file2 (in write mode) if it doesn’t exist in the present working directory. To add the contents at end of a file cat > file2 If any file with file name file3 exists in the current directory then it is overwritten with the contents of file1 & file2.

This command creates a new file file3 with the contents of file1 & file2 if file3 doesn’t exist in the present working directory. To concatenate files - adding the contents of two files into a new file or existing file cat >file2

This command simply prints the contents of file1 on the terminal screen. Note: After writing the text into the file, press ctrl+d to save and exit from the writing mode. If any file with file name file1 exists in the current directory then it is overwritten. This command creates a new file file1 (in write mode) if it doesn’t exist in the present working directory. To create files and write the data into them cat >file1 We cannot edit a file using the cat command. It is the most universal command/tool for creating files on Linux systems. All of them have their own purpose and benefits. There are mainly six ways of creating files in Linux.

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Or use cron to run your script regularly if you don't need to see output. So if you need to go back and read them, then write the output of diff to a file in the script. This will update every 2 seconds by default. Next you can either watch the differences on screen using watch watch. Make it write to a file if you want #!/bin/bash Write a bash script to find the differences, and update file2 touch check-differences.sh You have 1 file and you want to watch as changes are made to it: Play around with the interval of watch or other options for the commands below. You can use these methods to modify the behavior whatever way you want, such as writing the changes to a file to keep record. Here is a good trick to watch the differences as they happen in real time (or close) between 2 files or in one file being written to. Hat-tip to rgmarcha for pointing this out in the comments.įorget tailf, diff is the command you want. The editor (see also the discussion of LESSEDIT in PROMPTSġ. Line number will be displayed in the verbose prompt and in the =Ĭommand, and the v command will pass the current line number to The default (to use line numbers) mayĬause less to run more slowly in some cases, especially with a For example, +G causes less to initially display eachįile starting at the end rather than the beginning.įor really long logs, I find it convenient to use the -n option which turns off line numbering. Any command can be initialized on startup using the + option: +cmd Causes the specified cmd to be executed each time a new file isĮxamined. Key bindings are pretty much the same as in vi.

If I need to search for something, I type ^C to stop following the file and ? to start searching backwards. I prefer using less +FG 1 over tail -f because I find myself needing to search a log file for a specific error or ID.