| grep --perl-regexp '( | : http://bash.open-code.club/髮・81繝ｻ・｣繝ｻ9A%95繝ｻ89・ｰ繝ｻ・｡繝ｻ・ｨ髴托ｽｴ繝ｻ・ｾ/index.html | |
| grep --perl-regexp and empty match | Re: grep --perl-regexp and empty match : http://lists.gnu.org/archive/html/bug-gnu-utils/2003-07/msg00085.html | |
| grep --perl-regexp PATTERN | grep command examples ~ Linux IQ : http://linuxadministrative.blogspot.com/2014/06/grep-command-examples.html |