Can you search for and remove specific lines with Apache error_log?

Question

I know I am able to search for particular keywords in my Apache error_log file by using the grep command:

# grep "favicon.ico" error_log

I am curious though if it is possible to delete/remove any and all lines which contain specific keywords from a file.

I know this won't work but the idea is:

rm -r -f grep "favicon.ico" error_log

Answer 1

sed -i '/favicon.ico/d' error_log

But you can get rid of this error appearing in Apache error log by creating an empty favicon.ico file in document root or putting the following in the httpd.conf file:

Redirect 404 /favicon.ico

<Location /favicon.ico>
    ErrorDocument 404 "No favicon"
</Location>