How to add file in linux

How to append one file to another in Linux from the shell?

I have two files: file1 and file2 . How do I append the contents of file2 to file1 so that contents of file1 persist the process?

8 Answers 8

@BijayRungta: It sounds like you answered your own question. You’d pre-pend sudo to the cat command (and enter credentials if prompted).

you need to . chmod 777 /etc/default/docker to give yourself write permissions on that file — be sure to restore the old file permissions once done

@Sigur: Unless there’s a way to direct the output to two files at once, it would involve two invocations of the command.

@Sigur or have a look at the tee program: cat 1 | tee -a 2 3 . You can put as many files as you like after the —append (or -a for short) switch.

The >> operator appends the output to the named file or creates the named file if it does not exist.

This concatenates two or more files to one. You can have as many source files as you need. For example,

Update 20130902
In the comments eumiro suggests «don’t try cat file1 file2 > file1 .» The reason this might not result in the expected outcome is that the file receiving the redirect is prepared before the command to the left of the > is executed. In this case, first file1 is truncated to zero length and opened for output, then the cat command attempts to concatenate the now zero-length file plus the contents of file2 into file1 . The result is that the original contents of file1 are lost and in its place is a copy of file2 which probably isn’t what was expected.

Update 20160919
In the comments tpartee suggests linking to backing information/sources. For an authoritative reference, I direct the kind reader to the sh man page at linuxcommand.org which states:

Before a command is executed, its input and output may be redirected using a special notation interpreted by the shell.

While that does tell the reader what they need to know it is easy to miss if you aren’t looking for it and parsing the statement word by word. The most important word here being ‘before’. The redirection is completed (or fails) before the command is executed.

In the example case of cat file1 file2 > file1 the shell performs the redirection first so that the I/O handles are in place in the environment in which the command will be executed before it is executed.

A friendlier version in which the redirection precedence is covered at length can be found at Ian Allen’s web site in the form of Linux courseware. His I/O Redirection Notes page has much to say on the topic, including the observation that redirection works even without a command. Passing this to the shell:

. creates an empty file named out. The shell first sets up the I/O redirection, then looks for a command, finds none, and completes the operation.

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linux create file in directory

The easiest way to create a new file in Linux is by using the touch command. The ls command lists the contents of the current directory. Since no other directory was specified, the touch command created the file in the current directory.

1. Can mkdir create a file?
2. How do you create a file in a specific directory in Unix?
3. How do I add files to a folder?
4. How do you create a text file in Linux?
5. How do you create a directory?
6. What does P mean in Linux?
7. Can Touch create a directory?
8. What Linux command is used to list all files present in a directory?
9. How do I copy a file from one directory to another in Linux?
10. How do you move files in terminal?
11. How do I add a file in Linux?
12. How do you read a file in Linux?
13. How do I create a .TXT file?

Can mkdir create a file?

mkdir creates a file instead of directory.

How do you create a file in a specific directory in Unix?

1. touch command: It will create an empty file in directory specified. .
2. vi command (or nano): You can use any editor to create a file. .
3. cat command: Although cat is used to view file, but you can use this to create file as well from terminal.

How do I add files to a folder?

1. You must have a working copy of the directory. .
2. Create the new file inside your working copy of the directory.
3. Use `cvs add filename ‘ to tell CVS that you want to version control the file. .
4. Use `cvs commit filename ‘ to actually check in the file into the repository.

How do you create a text file in Linux?

1. Using touch to create a text file: $ touch NewFile.txt.
2. Using cat to create a new file: $ cat NewFile.txt. .
3. Simply using > to create a text file: $ > NewFile.txt.
4. Lastly, we can use any text editor name and then create the file, such as:

How do you create a directory?

1. Open Finder and navigate to the directory where you’d like to create the folder.
2. Click File in the upper-left corner of the screen.
3. Select New Folder in the drop-down menu that appears.
4. Name the folder, and then press Return .

What does P mean in Linux?

Linux Directories mkdir -p

It will create parent directory first, if it doesn’t exist. But if it already exists, then it will not print an error message and will move further to create sub-directories. This command is most helpful in the case when you don’t know whether a directory alredy exists or not.

Can Touch create a directory?

touch is not able to create directories, you need mkdir for that. However, mkdir has the useful -p / —parents option which creates a full directory structure. If you think you will need this more often and don’t want to type the path twice every time, you can also make a Bash function or a script for it.

What Linux command is used to list all files present in a directory?

The ls command is used to list files or directories in Linux and other Unix-based operating systems. Just like you navigate in your File explorer or Finder with a GUI, the ls command allows you to list all files or directories in the current directory by default, and further interact with them via the command line.

How do I copy a file from one directory to another in Linux?

‘cp’ command is one of the basic and most widely used Linux commands for copying files and directories from one location to another.
.
Common options for cp command:

Options	Description
-r/R	Copy directories recursively
-n	Don’t overwrite an existing file
-d	Copy a link file
-i	Prompt before overwrite

How do you move files in terminal?

If you use a visual interface like Finder (or another visual interface), you would have to click and drag this file into its correct location. In Terminal, you don’t have a visual interface, so you’ll have to know the mv command to do this! mv , of course stands for move.

How do I add a file in Linux?

The cat command is mainly used to read and concatenate files, but it can also be used for creating new files. To create a new file run the cat command followed by the redirection operator > and the name of the file you want to create. Press Enter type the text and once you are done press the CRTL+D to save the files.

How do you read a file in Linux?

1. Open the file using cat command.
2. Open the file using less command.
3. Open the file using more command.
4. Open the file using nl command.
5. Open the file using gnome-open command.
6. Open the file using head command.
7. Open the file using tail command.

How do I create a .TXT file?

1. The editor in your IDE will do fine. .
2. Notepad is an editor that will create text files. .
3. There are other editors that will also work. .
4. Microsoft Word CAN create a text file, but you MUST save it correctly. .
5. WordPad will save a text file, but again, the default type is RTF (Rich Text).

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Handbrake

On your Ubuntu desktop Activities toolbar, click the Ubuntu Software icon.In the following view, click on the search icon and enter Handbrake in the s.

Delete

How do I clear my Kubernetes eviction pods?How do you force delete a terminating pod?Can I delete evicted pods?Why did my pods get evicted?How do I de.

Latest news, practical advice, detailed reviews and guides. We have everything about the Linux operating system

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How to Create a File in Linux Using Terminal/Command Line

Creating a new file in Linux is straightforward, but there are also some surprising and clever techniques.

In this tutorial learn how to to create a file from a Linux terminal.

• Access to a command line/terminal window (Ctrl–Alt–F2 or Ctrl–Alt–T)
• A user account with sudo privileges (optional for some files/directories)

Creating New Linux Files from Command Line

Linux is designed to create any file you specify, even if it doesn’t already exist. One smart feature is that you can create a file directly, without needing to open an application first.

Here are a few commands for creating a file directly from the command line.

Create a File with Touch Command

The easiest way to create a new file in Linux is by using the touch command.

In a terminal window, enter the following:

This creates a new empty file named test.txt. You can see it by entering:

The ls command lists the contents of the current directory. Since no other directory was specified, the touch command created the file in the current directory.

If there’s already a file with the name you chose, the touch command will update the timestamp.

Create a New File With the Redirect Operator

A redirection operator is a name for a character that changes the destination where the results are displayed.

Right angle bracket >

This symbol tells the system to output results into whatever you specify next. The target is usually a filename. You can use this symbol by itself to create a new file:

This creates a new empty file.
Use the ls command to list the contents of the current directory and find the file test2.txt.

Create File with cat Command

The cat command is short for concatenate. It can be used to output the contents of several files, one file, or even part of a file. If the file doesn’t exist, the Linux cat command will create it.

To create an empty file using cat , enter the following:

Note the redirection operator. Typically, the command displays the contents of test2.txt on the screen. The redirection operator > tells the system to place it in the test2.txt file.

Verify that the file was created:

The system should now have test.txt, test2.txt, and test3.txt in the list.

Create File with echo Command

The echo command will duplicate whatever you specify in the command, and put the copy into a file.

echo 'Random sample text' > test4.txt

Verify that the file was created:

You should see the test4.txt file added to the list. Use the cat command to display the contents of the new file:

The system should display Random sample text (or whatever you entered with the echo command.)

Create File with printf Command

The printf command works like the echo command, and it adds some formatting functionality. To add a single line of text, enter:

printf 'First line of text\n' test5.txt

To add two lines of text, separate each line with the \n option:

printf 'First line of text\n Second line of text' test6.txt

You can use the cat command on either of these files to display their contents.

Note: To use several terminal instances in a single window manager, consider using Linux screen. It enables additional features and an enhanced command line for working with Linux files.

Using Text Editors to Create a Linux File

All Linux distributions have at least one text editor. Some have multiple editors. Each editor has different strengths and features. This will show you three of the most popular.

Vi Text Editor

Vi is the oldest text editor in Linux. It was created alongside the Linux operating system for directly editing text files. Since it’s unlikely you’ll see a Linux distribution without it, it’s a safe editor to know.

To create a file using Vi, enter the following:

Your screen will change. Now you’re in the text editor. Press the letter i to switch to insert mode, then type a few words to try it out.

To save and exit press Esc 😡 and hit Enter .

Vim Text Editor

You may have noticed that the Vi editor wasn’t very user-friendly. Vim is a newer version, which stands for Vi editor, Modified.

Use vim to create a new text file:

This screen will look similar to the Vi editor screen. Press i to insert text, and type a few words. Save file and exit by entering:

(Escape, colon wq, then Enter.)

Nano Text Editor

Nano is a newer and much easier text editor to navigate.

Create a new file by entering the command:

By default, Nano puts you directly into editing mode. It also displays a helpful list of commands at the bottom of the screen.

Enter some text, then press Ctrl+O to save the changes.

Press Ctrl+X to exit the editor.

Note: Learn all you need about Nano in the Install and Use Nano in Linux article.

Now you have several options to create new files in Linux from the command line. Next, learn how to copy files and directories in Linux to manage your files more efficiently.

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