{"id":240,"date":"2012-05-12T07:14:59","date_gmt":"2012-05-12T05:14:59","guid":{"rendered":"https:\/\/www.npcglib.org\/~stathis\/blog\/?p=240"},"modified":"2012-05-12T07:24:57","modified_gmt":"2012-05-12T05:24:57","slug":"linux-task-find-a-string-in-a-file-and-apply-an-operation-to-that-file","status":"publish","type":"post","link":"https:\/\/www.npcglib.org\/~stathis\/blog\/2012\/05\/12\/linux-task-find-a-string-in-a-file-and-apply-an-operation-to-that-file\/","title":{"rendered":"linux task: find a string in a file and apply an operation to that file"},"content":{"rendered":"

If you have a vast number of files and you want to do something with them, then use something like the following:<\/p>\n

\r\ngrep -l \"mystring\" * | xargs -I{} echo {}\r\n<\/pre>\n
this will echo<\/code> each filename that contains mystring<\/i> in the current working directory. You could replace echo<\/code> linux command with any other command, for instance with rm -f<\/code> to remove those files (be careful!). The -I{}<\/code> switch to xargs<\/code> prevents having problems with filenames that have spaces. If you want to search in a different directory than the working directory replace *<\/code> with it.<\/p>\n
So lets say you want to find files that contain DNS<\/i> in \/etc<\/i>. You can do this with:<\/p>\n
\r\ngrep -r -l \"DNS\" \/etc | xargs -I{} echo {}\r\n<\/pre>\n
If you want to find files that contain any form of some string<\/i> in \/home\/user<\/i>. You can do this with:<\/p>\n
\r\ngrep -i -r -l \"some string\" \/home\/user | xargs -I{} echo {}\r\n<\/pre>\n
where -i<\/code> (or –ignore-case<\/i>) does a case-insensitive search (i.e. it will match any some string<\/i>, or Some String<\/i>, etc.) and  -r<\/code> stands for recursive.<\/p>\n
If you have a complex scenario where you only want to process specific type of files or file patterns, you may want to use find<\/code> instead of grep<\/code> directly.<\/p>\n","protected":false},"excerpt":{"rendered":"
If you have a vast number of files and you want to do something with them, then use something like the following: grep -l “mystring” * | xargs -I{} echo {} this will echo each filename that contains mystring in the current working directory. You could replace echo linux command with any other command, for […]<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[5],"tags":[6],"yoast_head":"\n\n\n\n\t\n\t\n\t\n