Search engine files

Any ".search" file can be opened as search engine file, each line of which has one of the following formats:
[Engine name]:[url without '%s' inside]
[Engine name]:[url with '%s' as keyword]
[Engine name]:POST:[post params with '%s' as keyword]:[url]

Limitations (they are here for performance reasons):

Local engines

c:[command line with '%s' as keyword]
d:mimetype:[command line with '%s' as keyword]:[base url for external resources]