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shellvi

How can I use vi command in shell script?

I am using CentOS 6.7

I want open test.txt by vi and insert text "hihi" then save and quit from vi.

#! /bin/bash

vi test.txt << 'END'
i
hihi
press ESC
w
q
END

The result like this

Vim: Warning: Input is not from a terminal
Vim: Error reading input, exiting...
Vim: preserving files...
Vim: Finished.

How can I fix it?

Solution

  • There are many ways to create or modify text files, ranging from cat, to sed, to awk, to ed. I am going to assume, though, that you have a good reason for wanting to use vi.

    Try this command:

    echo $'ihihi\E:x\n' | vi test.txt

    In operation, this looks like:

    $ echo $'ihihi\E:x\n' | vi test.txt
Vim: Warning: Input is not from a terminal
$ cat test.txt
hihi

    I found this approach to be fragile: if vi experiences an error condition, no message will be seen.

    How it works

    We need to get vi to see an escape character. There are many ways to do that. I chose to use bash's $'...' strings as it allows escape to be entered as a simple two character string: \E. The steps that we use are:

    1. i introduces insert mode.

    2. The four characters hihi are entered into the buffer.

    3. Escape, \E, exits insert mode.

    4. :x\n exits with save.