Filtering lines in a text file?

Question

Content

There is a text file with lines like IP:Port
How to filter it, leaving only lines starting with 10.* and 172.*?

Answer 1

Write to icq: 559343705 - I will write for you for thanks

Answer 2

grep "^10." ip.txt?

Answer 3

If you are using Windows and the file is not very large, export it to Excel and sort and filter there.

Answer 4

Use regular expressions if you are familiar with them.
If you are interested in software implementation, then everything depends on the chosen programming language.

Answer 5

grep (or findstr on Windows)

Answer 6

I advise you to use perl, although in any language like C ++ it will be a program in several lines

Answer 7

cat + grep?

Answer 8

If you use powershell (it comes with new Windows starting with Vista, it is installed additionally on XP), then you can do this:
> cat .\file.txt | Select-String "172." > c:\output.txt
> cat .\file.txt | Select-String "10." >> c:\output.txt
Note that the second line uses a double ">" to indicate appending to the end of the file. A single character replaces the content, a double character appends to the end.