http://linuxcommando.blogspot.ca/2008/05/how-to-convert-text-files-to-all-upper.html
How can you convert a text file to all lower case or all upper case?
As usual, in Linux, there are more than 1 way to accomplish a task.
To convert a file (input.txt) to all lower case (output.txt), choose any ONE of the following:
- dd
$ dd if=input.txt of=output.txt conv=lcase
- tr
$ tr '[:upper:]' '[:lower:]' < input.txt > output.txt
- awk
$ awk '{ print tolower($0) }' input.txt > output.txt
- perl
$ perl -pe '$_= lc($_)' input.txt > output.txt
- sed
$ sed -e 's/(.*)/L1/' input.txt > output.txt
We use the backreference 1 to refer to the entire line and the L to convert to lower case.
To convert a file (input.txt) to all upper case (output.txt):
- dd
$ dd if=input.txt of=output.txt conv=ucase
- tr
$ tr '[:lower:]' '[:upper:]' < input.txt > output.txt
- awk
$ awk '{ print toupper($0) }' input.txt > output.txt
- perl
$ perl -pe '$_= uc($_)' input.txt > output.txt
- sed
$ sed -e 's/(.*)/U1/' input.txt > output.txt