Specifications

Chapter 18. TCP/IP
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18.2.4 Sample Program
main: ’ Main program
on error goto Err.TCP ’ Prepare for error interrupt (To Err.TCP
’ at the time of error occurrence)
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open "COM3:" as #hCom3% ’ Open a spread spectrum communications device
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’ Use the OPEN "COM3:" statement
sock.stts% = 1 ’ Set "1" to socket processing number
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call "socket.fn3" .fcTCnnSys interface% ’ Connect TCP/IP communications pathway
’ (system settings)
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’ Use SOCKET.FN3 function #41
sock.stts% = 2 ’ Set "2" to socket processing number
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call "socket.fn3" .fcSocket family%,type%,protocol%,sockfd% ’ Generate socket
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’ Use SOCKET.FN3 function #26
sock.stts% = 3 ’ Set "3" to socket processing number
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call "socket.fn3" .fcConnect sockfd%,family%,port%,serv.addr$ ’ Connect socket
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’ Use SOCKET.FN3 function #3
sock.stts% = 4 ’ Set "4" to socket processing number
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return ’
Err.TCP: ’ Error interrupt processing
’ Control transferred to this step if an
’ error occurs
err.code% = ERR ’ Get error number
err.line% = ERL ’ Get error line number
resume Sock.Err ’ RESUME statement to transfer control from
’ error interrupt processing to socket error
’ processing routine
Sock.Err: ’ Socket error processing routine
print " ERR : " ; hex$( err.code% ) ’ Display error number
print " ERL : " ; hex$( err.line% ) ’ Display error line number
if sock.stts% >= 3 then ’ If OK until socket generation,
call "socket.fn3" .fcClose sockfd% ’ close the socket
endif
if sock.stts% >= 2 then ’ If OK until connection of TCP/IP
’ communications pathway
call "socket.fn3" .fcTDiscnn interface% ’ disconnect the pathway
endif ’
if sock.stts% >= 1 then ’ If OK until opening the spread spectrum
’ communications device,
close #hCom3% ’ close the device
endif ’
goto main ’ To main program