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I'm a bit of a UNIX noob, but I'm trying to run the cat command to make a simple text file and it works great, however cat is never exited after making the file. For instance, I type cat > ~/mytextfile.txt and hit enter, the file is created but my cursor remains on a blank line.

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    cat is most often used for dumping the contents of one file into another, ex. cat file1 > file2 or feeding a file to a pipe, ex. cat file | somecommand. If you simply want to create an empty file, use the command touch. If you wish to create a new file with a few simple words, or append a few lines to an existing file, echo is a common solution. – Darth Android Jun 2 '10 at 11:20
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    @Darth - You should write your comment as an answer instead. – Nifle Jun 2 '10 at 11:56
  • "feeding a file to a pipe, ex. cat file | somecommand" 'cat'ting in this context, though commonly done, is completely useless. 'somecommand <file' is equivalent and runs one less process. The only way it might make sense would be to concatenate several files into a single input stream for 'somecommand' – JRobert Jun 2 '10 at 21:56
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You're telling cat to send nothing to a file. Use touch (as mentioned) instead.

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9

You have to send an EOF (^D) character on the standard input to tell cat to stop.

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  • I see, how can I get ^D? Or what is the shortcut or whatever? – skylerl Jun 2 '10 at 11:17
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    It is the key combination ctrl + d. – ayaz Jun 2 '10 at 11:29
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    Worth noting that lots of *nix command line apps (all the ones that read input from stdin) work the same way. – Chris Nava Jun 2 '10 at 17:45
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In my MAC I need to send EOF (^D) twice.

Example:

cat > /tmp/mypassword
RandomLettersAndNumbers123

Then press FN + Control + D twice.

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