bash sed examples

KnowHow_bash_sed.sh

#!/bin/bash

## composed sed usages

# soure a file into bash from java properties
#  1.sed removes emtpy lines
#  2.sed remove commented lines
#  3.sed removes windows eol

source <(cat <file> | sed --expression '/^[[:space:]]*$/d' | sed --expression '/^#.*$/d' | sed --expression 's/\r//g' )


## distinct usages

# replace all lines containing only whitespace chars
sed '/^[[:space:]]*$/d' <filename>

# remove all windows line endings
sed 's/\r//g' <filename>

# remove lines starting with #
sed --expression '/^#.*$/d'

# read from stdin
cat filename |sed --expression='s/x/y/g'