Add to file if exists and create if not

Question

I am working on a bash script that needs to take a single line and add it to the end of a file if it exists, and if it does not exist create the file with the line.

I have so far:

    if [ ! -e /path/to/file ]; then
        echo $some_line > /path/to/file
    else
        ???
    fi

How do I perform the operation that should go in the else (adding the line of text to the existing file)?

score 33 · Accepted Answer · answered Aug 11 '09 at 21:05

33

Use two angles: echo $some_line >> /path/to/file

answered Aug 11 '09 at 21:05

John Millikin

197,344
39
212
226

score 23 · Answer 2 · edited Jan 30 '17 at 16:30

23

> creates the file if it doesn't exist; if it exists, overwrites it.

>> creates the file if it doesn't exist; if it exists, appends to it.

if [ ! -e /path/to/file ]; then
   echo $some_line > /path/to/file
else
   echo $some_line >> /path/to/file
fi

edited Jan 30 '17 at 16:30

approxiblue

6,982
16
51
59

answered Aug 11 '09 at 21:15

firstthumb

4,627
6
35
45

6

use just echo $some_line >> /path/to/file will be sufficient since >> creates the file if it doesn't exist – ghostdog74 Aug 12 '09 at 23:47
Yes you are right. I just gave the sample to Mark Roddy as he did. – firstthumb Aug 13 '09 at 06:31

Add to file if exists and create if not

2 Answers2