| Server Programs Conclusion | ||
|---|---|---|
 | Chapter 10. Server Programs |  |
Server Programs Conclusion
Although the sample program is quite basic, it is actually very powerful. With minor
modifications it could easily send whichever file was requested. It could modify the header to
send the file name, size, date and time of last modification, and even optionally send the
data compressed and/or encrypted, using existing library code supplied with SIMPOL. With
minor modifications it could also provide a query mechanism where the client sends a
LIST command, for example, and it would then examine a designated
directory and return the file name and last modified date and time for each file to the
client. The client could then compare these with its own copy of each and request any file
that was newer than the copy it already holds (plus any missing ones). Using the ability of
the UTOSdirectoryentry object to set the date and time, the client could make
sure that the local copy always has the same date and time as the server one. This sort of
application could also be implemented as a web server program.