We can process and gather multiple strings using awk or sed as follows to save CPU cycle: It is possible to use it as a description on the delimiter. It’s useful and simple to use. The -e flag allows us to specify multiple patterns through repeated use. See also the -B and -C options. So far i can understand first part of your question , for that solution is to use either ” ^ ” or -v with the grep. In this article, we’re going to explore the basics of how to use regular expressions in the GNU version of grep, which is available by default in most Linux operating systems. Grep, which stands for "global regular expression print," is a powerful tool for matching a regular expression against text in a file, multiple files, or a stream of input. grep is one of the most useful and powerful commands in Linux for text processing.grep searches one or more input files for lines that match a regular expression and writes each matching line to standard output.. We can grep an exact match by putting a regex match of beginning(^) and ending($) char. grep multiple string patterns in many files I couldn't find a way to do this with a simple combination of the find and grep commands, but a friend suggested this grep/find command combination: grep -li "jtable" $(find . NOT logic is used to get results those do not matched given pattern. The answer posted by Cyrus is absolutely proper and is The Right Way TM to do it with grep if we only need to find files.When filenames need to additional parsing or operations on the matched filenames, we can resort to using while loop with if statement. grep -x “phoenix number3” * The output shows only the lines with the exact match. grep; awk; sed . I want to return line2 containing strings “not” and “summer” both. You can use option grep -i to make it case insensitive. I am using this command . In other words, use the grep command to search words or strings in a text files. I have the following being sent to my command line: find /base/dir1 /base/dir2 -type f -exec /x/y/z/grep -e lolol -e wow {} + This returns each file containing one or both of the supplied strings (lolol and wow).What I would like to do is to only return the files that contain both strings (AND not OR). But if you observe, this command failed to capture other lines containing … So you could either add an else clause if you want both "does" and "does not" prints, or you could just negate the if condition to only get failures. By default, grep displays the matching lines, and it may be used to search for lines of text matching one/many regular expressions in a fuss-free, and it … grep will return success if it finds at least one instance of the pattern and failure if it does not. Since we are planning to grep for "abcd", our command would be: # grep -E "^abcd$" /tmp/somefile abcd. grep -A num Print num lines of trailing context after each match. grep -L “pattern” file1 file2 file3. When we execute the grep command with specified pattern, if its is matched, then it will display the line of file containing the pattern without modifying the contents of the existing file. I have used -E and -i as well. sureshcisco: View Public Profile for sureshcisco: Find all posts by sureshcisco # 2 08-04-2010 girija. Hello , this is my first topic cause I need your little help I got .txt file, and I want to find lines without letter 'a', so im writing: grep "[^a]" list.txt (list.txt is the file of course) and i have no idea why it's not working because it shows lines with a. In other words, search and display all the lines, that do not match our strings or words; grep multiple strings using awk. By default with grep with have -e argument which is used to grep a particular PATTERN. Thank You. not 8th line2: This is not summer. But grep can not match a newline (it is an internal limitation that could only be avoided with the -z option). find {dir_path} -type f -exec grep “some string” {} /dev/null ; Never forget the saying: Here's an example where list of filenames comes from very commonly used find+while structure for safe parsing of filenames. A tool other than grep is the way to go.. line3: when is summer? This solution only works if you're not interested in the context, i.e. Say if you are already using the awk command or sed command command, then there is no need to pipe out to grep and feed data from grep. Luckily for you, there are multiple ways of finding text into files on Linux but the most popular command is the grep command. The grep command searches the given files for lines containing a match to a given pattern list. grep searches the named input FILEs (or standard input if no files are named, or if a single hyphen-minus (-) is given as file name) for lines containing a match to the given PATTERN.By default, grep prints the matching lines. search for a string in one or more files ----- grep 'fred' /etc/passwd # search for lines containing 'fred' in /etc/passwd grep fred /etc/passwd # quotes usually not when you don't use regex patterns grep null *.scala # search multiple files case-insensitive ----- grep -i joe users.txt # find joe, Joe, JOe, JOE, etc. The name grep comes from the ed (and vim) command “g/re/p”, which means globally search for a given regular expression and print (display) the output. @TC1 Whether grep -F has an actual performance benefit depends on the grep implementation: some of them apply the same algorithm anyway, so that -F makes a difference only to the time spent parsing the pattern and not to the time searching. See also the -A and -C options. Below is an example of using grep to make selecting multiple … – HelloGoodbye Sep 8 '15 at 14:20 This also doesn't work in the important (to me at least) case where the filename might contain the string beta . Method 1: grep for first and last character. If you want to display all lines that contain a sequence of four digits that is itself not part of any longer sequence of digits, one way is: grep -P '(?