Bash script to return lines matching a pattern and then count them?

AstralV

11/1/23, 7:43 PM

I'm trying to make a simple bash script to take user input and then search a .lst file for lines matching said input and then the count of matching lines. I'm pretty inexperienced with bash so I was wondering if anyone could point out what I'm doing incorrectly. Here's what I've got going on:

 echo "Enter pattern to be searched: "
 read pattern

 sed -n "/$pattern/p" "$file"
 sed -n "/$pattern/p" "$file" > file.lst

 echo "number of matching lines: "
 cat file.lst | wc -l

This returns matching lines when I write the specific filename in the script, but it doesn't work when I pass the filename as an argument and invoke it like

./script.sh myfile.lst

What am I doing incorrectly? Thanks ! I'm trying to find a solution that doesn't use awk or grep

1 + 2

bash

scripts

sed

steeldriver

11/1/23, 8:43 PM

Are you asking [How can I get a variable from terminal to use it in my script?](https://askubuntu.com/questions/398357/how-can-i-get-a-variable-from-terminal-to-use-it-in-my-script)

AstralV

11/1/23, 8:47 PM

yes please ! not sure what i'm doing wrong

Score:1

Ubuntu

AstralV

11/1/23, 8:58 PM

I figured it out lol, was making it needlessly complicated. The solution was to write

sed -n '/$pattern/p' $1

+ 0

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