{"id":244,"date":"2010-04-16T08:52:59","date_gmt":"2010-04-16T08:52:59","guid":{"rendered":"http:\/\/www.scmgalaxy.com\/tutorials\/2010\/04\/16\/unix-command-grep\/"},"modified":"2018-09-25T09:41:13","modified_gmt":"2018-09-25T09:41:13","slug":"unix-command-grep","status":"publish","type":"post","link":"https:\/\/www.devopsschool.com\/blog\/unix-command-grep\/","title":{"rendered":"Unix Command: Grep – Quick Reference – Pattern – Examples – Options"},"content":{"rendered":"

\"unix-command-grep\"<\/p>\n

Grep <\/b>scans its input for a pattern, and can display the selected pattern, the line numbers of the filenames where the pattern occurs, The command uses the following syntax
\n<\/i><\/span><\/span><\/p>\n

grep options pattern filesname(s)<\/i><\/span><\/u>
\n<\/span><\/span><\/p>\n

grep searches for pattern in one or more filenames.
\n<\/span><\/span><\/p>\n

Example for Grep<\/u> command: <\/span><\/span><\/b><\/p>\n

    \n
  1. grep \u201csales\u201d emp.lst<\/span><\/span><\/li>\n
  2. grep \u201cdirector\u201d emp1.lst emp2.lst<\/span><\/span><\/li>\n
  3. grep \u2018jai sharma\u2019 emp.lst<\/span><\/span><\/li>\n
  4. grep \u201cjai Sharma $var\u201d emp.lst<\/span><\/span><\/li>\n<\/ol>\n

    —————-Grep options—————————<\/b><\/span><\/span><\/p>\n

    Ignoring Case (i)<\/b> When you look for a name, but you are not sure of the case, grep offers the \u2013i (ignore) option which ignores case for patteen matching.<\/span><\/span><\/p>\n

    > Grep \u2013i \u2018agarwal\u2019 emp.lst<\/span><\/span><\/p>\n

    Deleting Lines\u00a0 or Inverse(-v):<\/b> -v (inverse) option selects all except lines containing the pattern. Thus, you can create a file other list containing all but director.<\/span><\/span><\/p>\n

    > Grep \u2013v \u201cdirector\u201d emp.lst > other list<\/span><\/span><\/p>\n

    Displaying line Numbers (-n): <\/b>The \u2013n(number) options displays the line numbers containing the pattern, along with the lines:<\/span><\/span><\/p>\n

    > grep \u2013n \u2018marketing\u2019 emp.lst<\/span><\/span><\/p>\n

    Counting Line Containing patterns (-c):<\/b> The \u2013c (count) option counts the number of lines containing the pattern ( which is not the same as number of occurrences).<\/span><\/span><\/p>\n

      \n
    1. grep \u2013c director emp.lst<\/span><\/span><\/li>\n
    2. grep \u2013c director emp*.lst<\/span><\/span><\/li>\n<\/ol>\n

      Displaying Filenames (-l):<\/b> The \u2013l (list) option displays only the files names of files containing the pattern.<\/span><\/span><\/p>\n

      > grep \u2013l \u2018manager\u2019 *.lst<\/span><\/span><\/p>\n

      Matching Multiple Patterns(-e):<\/b> With the \u2013e option, you can match the three agarwals by using grep like this:<\/span><\/span><\/p>\n

      > grep \u2013e \u201cAgarwal\u201d \u2013e \u201caggarwal\u201d \u2013e \u201cagarwal\u201d emp.lst<\/span><\/span><\/p>\n

      Taking patterns from a file (-f):<\/b> we can place all patterns in a separate file, one pattern per lin. Grep takes inputs from there with the \u2013f option:<\/span><\/span><\/p>\n

      > grep \u2013f pattern.lst emp.lst<\/span><\/span><\/p>\n

      \u00a0<\/span><\/span><\/p>\n","protected":false},"excerpt":{"rendered":"

      Grep scans its input for a pattern, and can display the selected pattern, the line numbers of the filenames where the pattern occurs, The command uses the following syntax grep options pattern filesname(s) grep searches for pattern in one or more filenames. Example for Grep command: grep \u201csales\u201d emp.lst grep \u201cdirector\u201d emp1.lst emp2.lst grep \u2018jai…<\/p>\n","protected":false},"author":1,"featured_media":4369,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_kad_post_transparent":"","_kad_post_title":"","_kad_post_layout":"","_kad_post_sidebar_id":"","_kad_post_content_style":"","_kad_post_vertical_padding":"","_kad_post_feature":"","_kad_post_feature_position":"","_kad_post_header":false,"_kad_post_footer":false,"_kad_post_classname":"","_joinchat":[],"footnotes":""},"categories":[4957],"tags":[4126,333,475,4124,4128,4129,4131,4130,4121,4123,169,4125,4127,4122],"class_list":["post-244","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-linux","tag-basic-grep-commands","tag-command","tag-grep","tag-grep-command-line-options","tag-grep-unix-command-guide","tag-grep-unix-command-introduction","tag-grep-unix-command-overview","tag-grep-unix-command-quick-reference","tag-grep-unix-commands-with-examples","tag-how-to-use-grep","tag-unix","tag-unix-command-grep-examples","tag-unix-grep-command-match-pattern","tag-unix-grep-command-options"],"_links":{"self":[{"href":"https:\/\/www.devopsschool.com\/blog\/wp-json\/wp\/v2\/posts\/244","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.devopsschool.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.devopsschool.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.devopsschool.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.devopsschool.com\/blog\/wp-json\/wp\/v2\/comments?post=244"}],"version-history":[{"count":3,"href":"https:\/\/www.devopsschool.com\/blog\/wp-json\/wp\/v2\/posts\/244\/revisions"}],"predecessor-version":[{"id":4372,"href":"https:\/\/www.devopsschool.com\/blog\/wp-json\/wp\/v2\/posts\/244\/revisions\/4372"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.devopsschool.com\/blog\/wp-json\/wp\/v2\/media\/4369"}],"wp:attachment":[{"href":"https:\/\/www.devopsschool.com\/blog\/wp-json\/wp\/v2\/media?parent=244"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.devopsschool.com\/blog\/wp-json\/wp\/v2\/categories?post=244"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.devopsschool.com\/blog\/wp-json\/wp\/v2\/tags?post=244"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}