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deepblue_86
Asked: 2016-04-01 22:44:01 +0800 CST

grep command for a text file in multiple directories

  • 772

I have 24 directories in a specific directory (main_directory). Each 24 directory have a text file whose name is DATA.txt.

I need to use grep command to extract below specific pattern for each text file; 

2* x  = 3800689.6402     y  = 882077.3636     z  = 5028791.2953

2* x = part is constant for all DATA.txt. The other numeric numbers are variable. I need to extract above line for each DATA.txt and save them into another text file. Which script I can use for this process?

command-line

3 Answers

  1. Best Answer

    To recursively search using grep, use the -R option.

    To search for an exact string, use -F, so that 2* isn't treated as a regular expression.

    To search only on specific filenames, use the --include option. Combined:

    grep -FR --include=DATA.txt '2* x' main_directory > another_text_file
    • 11

  2. Since you know the name of the target files, you can also do

    grep '^2\* x' */DATA.txt > newfile

    Or, with awk:

    awk '^/2\* x/' */DATA.txt > newfile

    And Perl:

    perl -ne 'print if /2\* x/' */DATA.txt > newfile
    • 5

  3. General approach:

    grep -r <pattern>

    or

    specific approach:

    find -name <file patterns which you want to find> | xargs grep <pattern you looking for>
    • 1