Counting line in text file

ok to count the number of lines in a text file I have to

wc -l filename.txt rite? but then how do i get it to out put this as an integer?

it out puts
linecount filename.txt

so lets say file.txt has 30 lines it out puts
30 file.txt how do i get it to out put only 30

thx

1. Make it read from stdin (using redirection) so it doesn't print a filename
2. Use the back-quotes to capture the stdout of a process

Like so

Code:

---

a=`wc -l < file.txt`
echo $a

---

dude your really good, how long have u been using linux?

grep -n .\* in-file > out-file