Search for a pattern at the beginning of a line using grep

$ps -e “kworker$” error: unknown sort specifier Usage: ps [options] Try ‘ps –help ‘ or ‘ps –help ‘ for additional help text. For more details see ps(1). $ps -ef | grep “^daemon” daemon 639 1 0 May04 ? 00:00:00 /usr/sbin/atd -f $ps -ef | grep “^rtkit” rtkit 1245 1 0 May04 ? 00:00:00 /usr/lib/rtkit/rtkit-daemon $ps …

Indicate how each name would be interpreted if used as a command name

$type -a locate locate is /usr/bin/locate $type -a ls ls is aliased to `ls –color=auto’ ls is /bin/ls $type -t ls alias $type -t locate file $type -t /dev/urandom $type -t /dev/sda1 $type -t urandom $type -t sda1 $type -t type builtin $type -t shuf file $type -t bash file $type -t proc $type -t …

fold: Wrap input lines to fit in specified width

$cat test.pl use strict; use File::Rename (); use Pod::Usage; main() unless caller; sub main { my $options = File::Rename::Options::GetOptions or pod2usage; mod_version() if $options->{show_version}; pod2usage( -verbose => 2 ) if $options->{show_manual}; pod2usage( -exitval => 1 ) if $options->{show_help}; @ARGV = map {glob} @ARGV if $^O =~ m{Win}msx; File::Rename::rename(\@ARGV, $options); } sub mod_version { print __FILE__ …