How to check a file exists

Question

How do I determine that a file exists using a shell script?

I.e:

#!/bin/sh

if [ Does File Exist? ]
then
    do this thing
fi

Answer 1

You probably want /bin/bash unless you need to use /bin/sh, /bin/sh is more restricted. So if you are using bash:

Like so:

 if [[ -e filename ]]; then
    echo 'exists'
 fi

If your filename is in a variable, then use the following, the double quotes are important if the file has a space in it:

if [[ -e "$myFile" ]]; then
   echo 'exists'
fi

If you are using sh, and want to be compatible with the IEEE Std 1003.1,2004 Edition, then use single brackets instead. The -e switch is still supported.

Answer 2

http://tldp.org/LDP/abs/html/fto.html

Answer 3

if [ -f filename ]

will test for the existence of a regular file. There are other switches you can pass it to check for an executable or other attributes of a file.

Answer 4

Reference page for file testing

Once you run through all those pages,
Keep this Reference sheet handy.

Answer 5

There is always the man pages:

man test

Answer 6

Just to note that if you want something that works across all sh shells (not only bash) and cross-platform, the only way is:

ls filename >/dev/null 2>&1
if [ $? = 0 ]; then
   echo "File exists"
fi