Can I use two grep in Linux?
Grep AND using Multiple grep command You can also use multiple grep command separated by pipe to simulate AND scenario. The following example will grep all the lines that contain both “Manager” and “Sales” in the same line.
How efficient is grep?
Typically grep is an efficient way to search text. However, it can be quite slow in some cases, and it can search large files where even minor performance tweaking can help significantly.
How grep is so fast?
GNU grep is fast because it AVOIDS LOOKING AT EVERY INPUT BYTE. GNU grep is fast because it EXECUTES VERY FEW INSTRUCTIONS FOR EACH BYTE that it does look at.
Is grep case sensitive?
Case Insensitive Search By default, grep is case sensitive. This means that the uppercase and lowercase characters are treated as distinct. To ignore case when searching, invoke grep with the -i option (or –ignore-case ).
Is grep or awk faster?
When only searching for strings, and speed matters, you should almost always use grep . It’s orders of magnitude faster than awk when it comes to just gross searching.
Does grep run in parallel?
The benefit of parallel grep will be noticable when doing repeated grep on the same directory tree, for example, for different keywords in the same source code. The file contents will be cached in RAM (well, depending on how much RAM and source code you have, of course).
Why is grep taking so long?
There are many reasons why your process could be slow, heavy load on the disk, a slow nfs if you use it, extremely long lines to parse, without more information on the input file and the system you are running this on, it is hard to say why it is so slow.
Why is grep slow?
If you’re running grep over a very large number of files it will be slow because it needs to open them all and read through them. If you have some idea of where the file you’re looking for might be try to limit the number of files that have to be searched through that way.
Why grep so fast?
> #1 trick: GNU grep is fast because it AVOIDS LOOKING AT EVERY INPUT BYTE. You stop looking at entire files, which can avoid a lot of bytes to go through.
Does grep match case?
By default, grep is case sensitive. This means that the uppercase and lowercase characters are treated as distinct. To ignore case when searching, invoke grep with the -i option (or –ignore-case ).
Why is awk better than grep?
Grep and awk can be used at the same time to narrow down the search enhance results. Grep is a simple tool to use to quickly search for matching patterns but awk is more of a programming language which processes a file and produces an output depending on the input values.
How do I grep multiple patterns in Linux?
How to Grep Multiple Patterns – Syntax The basic grep syntax when searching multiple patterns in a file includes using the grep command followed by strings and the name of the file or its path. The patterns need to be enclosed using single quotes and separated by the pipe symbol. Use the backslash before pipe | for regular expressions.
How to grep only the line that contains both strings?
When the both strings are in sequence then put a pattern in between on grep command: Example if the following lines are contained in a file named Dockerfile: To get the line that contains the strings: FROM python and as build-python then use: Then the output will show only the line that contain both strings: Show activity on this post.
What is grep in Linux?
The name stands for Global Regular Expression Print. By using the grep command, you can customize how the tool searches for a pattern or multiple patterns in this case. You can grep multiple strings in different files and directories.
How to use Git grep to combine multiple patterns?
Here is the syntax using git grep combining multiple patterns using Boolean expressions: The above command will print lines matching all the patterns at once. –no-index Search files in the current directory that is not managed by Git.