useful bash utilities

useful_bash_utilities.sh

# grep for multiple patterns and replace a pattern (or leave 'bar' empty to remove that pattern)
grep 'pattern1\|pattern2\|pattern3' file | sed 's/foo/bar/g'

# list directoy, grab date, time, and filename, sort by most recent
ls -l | awk '{print $6, $7, $8, $9}' | sort --reverse

# if you only want to ls by time
# add -ltr for reverse
ls -lt

# run process in background without exiting on terminal exit
nohup myprogram > myprogram.out &

# get the disk usage of a directory
du -sh path/to/folder

# get number of processors
grep -c ^processor /proc/cpuinfo