Thanks! BrowserUk. Actually I have no any idea about data transfer in perl. Now first thing I'm a little confused is how to check a variable length data packet correctly. It seems I can use 2 ways below to treat it:

  1. read 4bytes to know size of packet, reset length parameter, read rest of it and check end char and checksums
  2. read data in a loop, if there is no any data received in a time (e.g 3 sec) or read function return 0, check if last 2 bytes are correct checksum and end char.
So am I on the right way? Which way above is better or correct? Is there any codes in modern perl about data transit in network or serial for reference? Please help

Again, apologies for my poor english I hope i express my question clear enough.



I am trying to improve my English skills, if you see a mistake please feel free to reply or /msg me a correction

In reply to Re^8: deal data transfer by xiaoyafeng
in thread deal data transfer by xiaoyafeng

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