it may be in C, Java, C++, C#
The virus signatures used can be made up by you. However, they must have a minimum size of 10 bytes.
code should at a min be able to search files that match the search criteria in the working directory. It may have a feature to scan the sub-tree of files and directories with the current directory as the root of the tree. It should handle errors like no access to file or so, etc
It should take the vir-us signat-ures to sea-rch from a file of virus signat-ures (which may have any format which you like, scan-ner must be able to dete-ct the presen-ce of any given signat-ure in the file-s being sear-ched).
On discove-ring an infec-ted file the code should keep a list of all infect-ed fi-les it comes acro-ss and outp-uts to the user the list when scann-ing has completed or with a message that it is finiched scanng nd no viruses hav found.
It is just a small work for some 1 whois professional!