Method of treating whitespace during virus detection

Abstract

A method is provided for detecting computer viruses that infect text-based files. In accordance with a preferred embodiment, a collection of virus signatures reflecting sequences of characters or instructions known to be found in such viruses is maintained on a computer system. A virus detection program is also maintained for the purpose of comparing the contents of computer files to the virus signatures. Upon execution of the virus detection program, whitespace within text-based files is transformed such that each sequence of whitespace characters is replaced by a single whitespace character. Virus signatures of viruses known to infect text files are similarly transformed. A transformed text-based file is then searched for at least one of said virus signatures. The user is alerted to a possible virus infection if any of the virus signatures are found in a file. In another preferred embodiment, an additional collection of at least one virus signature containing sequences of characters or instructions known to be found in viruses that infect executable computer files is maintained on the computer system. A transformed text-based file is searched for at least one of the additional virus signature, which are not transformed before the search.