Send a 4-byte Length Prefix over a Socket

See more Socket/SSL/TLS Examples

Demonstrates Socket.SendCount, which sends a four-byte length prefix in network byte order. This is typically used to tell the peer how many bytes follow.

integer li_rc
integer li_Success
oleobject loo_Socket
integer li_BTls
integer li_MaxWaitMs
integer li_MessageLength

li_Success = 0

loo_Socket = create oleobject
li_rc = loo_Socket.ConnectToNewObject("Chilkat.Socket")
if li_rc < 0 then
    destroy loo_Socket
    MessageBox("Error","Connecting to COM object failed")
    return
end if

//  Connect to the server using TLS.
li_BTls = 1
li_MaxWaitMs = 5000
li_Success = loo_Socket.Connect("example.com",5000,li_BTls,li_MaxWaitMs)
if li_Success = 0 then
    Write-Debug loo_Socket.LastErrorText
    destroy loo_Socket
    return
end if

//  Send a four-byte length prefix in network byte order.  A common framing pattern is to send the
//  number of bytes in a message before the message itself, so the peer knows exactly how many bytes
//  to read.
li_MessageLength = 512
li_Success = loo_Socket.SendCount(li_MessageLength)
if li_Success = 0 then
    Write-Debug loo_Socket.LastErrorText
    destroy loo_Socket
    return
end if

Write-Debug "Length prefix sent."


destroy loo_Socket