Linux/Unix: Find Command Ignore Case Insensitive Search

last updated in Categories , , , ,

I am a new Linux and Unix-command line user. I am using find command to search file called “fooBar.conf.sample” in my home directory. I do not know the case, it could be uppercase, lowercase, or a mix of both. How can search a file and ignore case on a Linux or Unix-like system?

The find command recursively descends the directory tree for each path provided, evaluating an expression. It is mainly used to search files and directories on Linux and Unix-like systems. The syntax is as follows to search files according to given criteria. You can search for files by name, owner, group, type, permissions, date, and other criteria:

find dir-to-look criteria what-to-do

OR

find [options] dir-to-look criteria what-to-do

In this example, search your $HOME for a file called hello.c:

find $HOME -name "hello.c" -print

This will search the whole $HOME (i.e. /home/username/) system for any files named “hello.c” and display their pathnames:

/Users/vivek/Downloads/hello.c
/Users/vivek/hello.c

However, it will not match HELLO.C or HellO.C. To match is case insensitive pass the -iname option as follows:

find $HOME -iname "hello.c" -print

Sample outputs:

/Users/vivek/Downloads/hello.c
/Users/vivek/Downloads/Y/Hello.C
/Users/vivek/Downloads/Z/HELLO.c
/Users/vivek/hello.c

Finally, pass the -type f option to only search for files:

find /dir/to/search -type f -iname "fooBar.conf.sample" -print
find $HOME -type f -iname "fooBar.conf.sample" -print

A note about AIX/HP-UX and other old Unix-like systems

The -iname works either on GNU or BSD (including OS X) version find command. If your version of find command does not supports -iname, try the following syntax using grep command:

find $HOME | grep -i "hello.c"
find $HOME -name "*" -print | grep -i "hello.c"

OR try

find $HOME -name '[hH][eE][lL][lL][oO].[cC]' -print

Sample outputs:

/Users/vivek/Downloads/Z/HELLO.C
/Users/vivek/Downloads/Z/HEllO.c
/Users/vivek/Downloads/hello.c
/Users/vivek/hello.c
See also

Posted by: Vivek Gite

The author is the creator of nixCraft and a seasoned sysadmin, DevOps engineer, and a trainer for the Linux operating system/Unix shell scripting. Get the latest tutorials on SysAdmin, Linux/Unix and open source topics via RSS/XML feed or weekly email newsletter.

2 comment

  1. the locate command fines file on a system. adding -i has it ignore case

    locate -i hello.c

    However it will also find directories with the same name that can produce a long for something like “hello” to prevent this use something like this

    locate -ir /hello.c$

    That will locate a the exact but case insensitive filename “hello.c”

  2. Thanks. Very useful. I also found that with the locate command, you can add a parameter -i to ignore case

    Have a question? Post it on our forum!

Tagged as: Tags