Kbase P114232: Application using 4GL Socket does not read all the data
| Autor |
Progress Software Corporation - Progress |
| Acesso |
Público |
| Publicação |
11/5/2009 |
|
Status: Verified
SYMPTOM(s):
Application using 4GL Socket does not read all the data
The number at bytes available at the 4GL Socket is incorrect
A 4GL Socket connection returns 0 bytes in the read handler procedure
FACT(s) (Environment):
Using the GET-BYTES-AVAILABLE() method in a loop to determine the amount of bytes to read
The 4GL Socket application is communicating with a Web Server
All Supported Operating Systems
Progress 9.1x
OpenEdge 10.x
CAUSE:
The Web Server is sending the response in multiple TCP packets. If the loop in which data is read goes too fast, then the next TCP packet is missed.
FIX:
Specify a timeout for the READ() method and read the data until the BYTES-READ attribute returns 0.
The following is not a complete working sample, but it illustrates the method:
vSocket:SET-SOCKET-OPTION("SO-RCVTIMEO", '5').
SET-SIZE(mBuffer) = iBuf + 1.
SET-BYTE-ORDER(mBuffer) = BIG-ENDIAN.
vSocket:READ(mBuffer, 1, iBuf, 1) NO-ERROR.
cStr = cStr + GET-STRING(mBuffer,1).
SET-SIZE(mBuffer) = 0.
iLength = vSocket:BYTES-READ.
tLength = iLength.
IF iLength > 0 THEN
DO:
DO WHILE iLength > 0.
SET-SIZE(mBuffer) = iBuf + 1.
SET-BYTE-ORDER(mBuffer) = BIG-ENDIAN.
vSocket:READ(mBuffer, 1, iBuf, 1) NO-ERROR.
cStr = cStr + GET-STRING(mBuffer,1).
SET-SIZE(mBuffer) = 0.
iLength = vSocket:BYTES-READ.
tLength = tLength + iLength.
END.