| Remove blank lines from a file | sed /^$/d |
| Remove CRLF from a file | tr -d '\n' < file |
| Remove leading whitespace | sed 's/^[ ]*//' # The line has 1 space and 1 tab between the []. |
| Remove trailing whitespace | sed 's/[ ]*$//' # The line has 1 space and 1 tab between the []. |
| Upper Case | tr "[:lower:]" "[:upper:]" < filename |
| Lower Case | tr "[:upper:]" "[:lower:]" < filename |
sed Commands