{"id":92,"date":"2011-03-22T04:23:13","date_gmt":"2011-03-21T18:23:13","guid":{"rendered":"http:\/\/helms-deep.net\/~rwh\/blog\/?p=92"},"modified":"2011-03-31T21:45:38","modified_gmt":"2011-03-31T11:45:38","slug":"bash-guide-for-beginners-chapter-4-solutions","status":"publish","type":"post","link":"https:\/\/helms-deep.net\/~rwh\/blog\/?p=92","title":{"rendered":"Bash Guide for Beginners, chapter 4 solutions"},"content":{"rendered":"<p>Solutions to:<\/p>\n<p><a href=\"http:\/\/tldp.org\/LDP\/Bash-Beginners-Guide\/html\/sect_04_05.html\">http:\/\/tldp.org\/LDP\/Bash-Beginners-Guide\/html\/sect_04_05.html<\/a><br \/>\n1. <\/p>\n<pre lang=\"bash\">grep bash \/etc\/passwd | cut -d: -f1<\/pre>\n<p>2. <\/p>\n<pre lang=\"bash\">grep \"^daemon\" \/etc\/group<\/pre>\n<p>3. <\/p>\n<pre lang=\"bash\">grep --invert-match \"^daemon\" \/etc\/group<\/pre>\n<p>4. info with line numbers:<\/p>\n<pre lang=\"bash\">grep -n localhost \/etc\/hosts<\/pre>\n<p>number of occurrences of string:<\/p>\n<pre lang=\"bash\">grep -o localhost \/etc\/hosts |wc -w<\/pre>\n<p>5. <\/p>\n<pre lang=\"bash\">cd \/usr\/share\/doc\r\nfor file in *\r\ndo\r\n\tif grep \"$file\" \/etc\/shells &gt; \/dev\/null\r\n\tthen\r\n\t\techo \"$file\"\r\n\tfi\r\ndone<\/pre>\n<p>6. <\/p>\n<pre lang=\"bash\">sum=0\r\nfor file in *\r\ndo\r\n\tif grep \"$file\" \/etc\/shells &gt; \/dev\/null\r\n\tthen\r\n\t\tsum=`expr $sum + $(find \"$file\" -name README |wc -l)`\r\n\tfi\r\ndone\r\necho $sum<\/pre>\n<p>7. <\/p>\n<pre lang=\"bash\">find . -mtime 0.42 -type f\r\nfor file in *\r\ndo\r\n\tif [ `stat -c %Y \"$file\"` -gt `expr $(date \"+%s\") - 36000` ] &amp;&amp; [ -f \"$file\" ]\r\n\tthen\r\n\t\techo \"$file\"\r\n\tfi\r\ndone<\/pre>\n<p>8.<\/p>\n<p>9. <\/p>\n<pre lang=\"bash\">grep -c \".*\" test<\/pre>\n<p>10. <\/p>\n<pre lang=\"bash\">grep \"^\/dev\" \/etc\/fstab | awk '{print $1}'\r\ngrep -o \"^\/dev[^[:space:]]*\" \/etc\/fstab<\/pre>\n<p>11. <\/p>\n<pre lang=\"bash\">user=rwh\r\nif grep \"^$user:\" \/etc\/passwd &gt; \/dev\/null\r\nthen\r\n\techo user $user exists in the fstab\r\nelse\r\n\techo user $user does not exist in the fstab\r\nfi<\/pre>\n<p>12. <\/p>\n<pre lang=\"bash\">cd \/etc\r\nls |grep [0-9]\r\nls |grep \"[[:digit:]]\"<\/pre>\n","protected":false},"excerpt":{"rendered":"<p>Solutions to: http:\/\/tldp.org\/LDP\/Bash-Beginners-Guide\/html\/sect_04_05.html 1. grep bash \/etc\/passwd | cut -d: -f1 2. grep &#8220;^daemon&#8221; \/etc\/group 3. grep &#8211;invert-match &#8220;^daemon&#8221; \/etc\/group 4. info with line numbers: grep -n localhost \/etc\/hosts number of occurrences of string: grep -o localhost \/etc\/hosts |wc -w &hellip; <a href=\"https:\/\/helms-deep.net\/~rwh\/blog\/?p=92\">Continue reading <span class=\"meta-nav\">&rarr;<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_monsterinsights_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0,"footnotes":""},"categories":[35,33],"tags":[],"class_list":["post-92","post","type-post","status-publish","format-standard","hentry","category-answers","category-scripting"],"_links":{"self":[{"href":"https:\/\/helms-deep.net\/~rwh\/blog\/index.php?rest_route=\/wp\/v2\/posts\/92","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/helms-deep.net\/~rwh\/blog\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/helms-deep.net\/~rwh\/blog\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/helms-deep.net\/~rwh\/blog\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/helms-deep.net\/~rwh\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=92"}],"version-history":[{"count":8,"href":"https:\/\/helms-deep.net\/~rwh\/blog\/index.php?rest_route=\/wp\/v2\/posts\/92\/revisions"}],"predecessor-version":[{"id":94,"href":"https:\/\/helms-deep.net\/~rwh\/blog\/index.php?rest_route=\/wp\/v2\/posts\/92\/revisions\/94"}],"wp:attachment":[{"href":"https:\/\/helms-deep.net\/~rwh\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=92"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/helms-deep.net\/~rwh\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=92"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/helms-deep.net\/~rwh\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=92"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}