count all occurrences of string in lots of files with grep

Question

I have a bunch of log files. I need to find out how many times a string occurs in all files.

grep -c string *

retruns

...
file1:1
file2:0
file3:0
...

Using pipe I was able to get only files that have one or more occurrence:

grep -c string * | grep -v :0

...
file4:5
file5:1
file6:2
...

How to get only the combined count? (If it returns file4:5, file5:1, file6:2 I want to get back 8.)

Answer 1

Instead of using -c, just pipe it to wc -l.

grep string * | wc -l

This will list each occurrence on a single line and then count the number of lines.

This will miss instances where the string occurs 2+ times on one line, though.

Answer 2

cat * | grep -c string

Answer 3

cat * | grep -c string

One of the rare useful applications of cat.

Answer 4

This works for multiple occurrences per line:

grep -o string * | wc -l