I use md5sum a lot, often on network-filesystem-accessed files so that readers can be sure they are reading files after writers have completed. The performance of md5sum is generally acceptable, but for large (gigabyte+) files even on a fast (1 Gbps) LAN, the performance would be considerably better if I could specify on the command line a buffer size to use. I imagine the md5sum code using this value in a setvbuf call. I use this technique (setting larger buffer sizes for network-accessed files) frequently and know md5sum and other utilities would benefit from it.
Scott Nichol
