sending a jpeg image to a Client.

In what medium are you sending these? Mailslots, named pipes, memory-mapped files, disk files, email, sockets, or HTTP? Did you write an automated FTP client? If you just want to know how to stuff multiple pieces of standalone data into a single stream or buffer, that's easy. You need to conjure a format or protocol of your own. This can be very simple. Here's one that I like to use. I use a CRC32 for the checksum, but you can eliminate that completely if you want. Some mediums need it (telephony), and others don't (tcp/ip). The size is important, though. It tells you where each block begins and ends. If you put them all at the beginning of the stream, you don't have to do a lot of SEEKing in the stream to find your way around. But if your stream is read-only of you write on-the-fly, you can put the SIZE between the datablocks instead of all of them at the beginning. The key is that the client reads the stream the same way the server writes it. --------stream start number of blocks (one image per block) (4 bytes) block1size (4 bytes) block1checksum (4 bytes) block2size (4 bytes) block2checksum (4 bytes) ... ... blocknsize (4 bytes) blocknchecksum (4 bytes) block1data (block1size bytes) block2data (block2size bytes) ... blockndata (blocknsize bytes) -----------stream end

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spgilmore23y ago
In what medium are you sending these? Mailslots, named pipes, memory-mapped files, disk files, email, sockets, or HTTP? Did you write an automated FTP client? If you just want to know how to stuff multiple pieces of standalone data into a single stream or buffer, that's easy. You need to conjure a format or protocol of your own. This can be very simple. Here's one that I like to use. I use a CRC32 for the checksum, but you can eliminate that completely if you want. Some mediums need it (telephony), and others don't (tcp/ip). The size is important, though. It tells you where each block begins and ends. If you put them all at the beginning of the stream, you don't have to do a lot of SEEKing in the stream to find your way around. But if your stream is read-only of you write on-the-fly, you can put the SIZE between the datablocks instead of all of them at the beginning. The key is that the client reads the stream the same way the server writes it. --------stream start number of blocks (one image per block) (4 bytes) block1size (4 bytes) block1checksum (4 bytes) block2size (4 bytes) block2checksum (4 bytes) ... ... blocknsize (4 bytes) blocknchecksum (4 bytes) block1data (block1size bytes) block2data (block2size bytes) ... blockndata (blocknsize bytes) -----------stream end