


Introducing how to use the grep command to display context information under Linux
This article mainly studies the related content of grep displaying several lines of information before and after under Linux, as follows.
Grep under standard unix/linux controls the context through the following parameters grep -C 5 foo file displays the line matching the foo string in the file file and the upper and lower 5 lines grep -B 5 foo file displays foo and the first 5 lines grep -A 5 foo file Display foo and the next 5 lines to check the grep version number is grep -V. If you want to upgrade, the upgrade method: the latest source code (Google or Baidu search homepage), compile and install it somewhere, such as /home/ aaa/bin/ Then use /home/aaa/bin/grep when using it in the future, or just add /home/aaa/bin to the PATH environment variable.
grep under standard unix/linux controls the context through the following parameters
grep -C 5 foo file 显示file文件里匹配foo字串那行以及上下5行 grep -B 5 foo file 显示foo及前5行 grep -A 5 foo file 显示foo及后5行
The way to check the grep version number is
grep -V
If you want to upgrade, the upgrade method: the latest source code (google or Baidu search homepage), compile and install it somewhere, such as /home/aaa/bin/, then use /home/aaa/ when you use it in the future. bin/grep, or add /home/aaa/bin to the PATH environment variable. Assuming you overwrite the latest compiled grep to the folder where your current grep is located, the upgrade will naturally be completed.
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