The missing information:
1) Linux system, \R = \n
2) Files are opened O_RDONLY, no writing
3) All IO in this module is either buffered or all 'sys'; no mixing of the two
4) I have added code to do a sysseek to 0,CUR and compared that which the computed offset. This has not yet fired, to indicate a failed seek. But I have removed all the buffered mode code.
5) The files are continuous. They were created from text databases with shell utilities
6) Possibly relevant is that this module is running in multiple processes, potentially at the same time. But simultanious reads should not be a problem....

It is always better to have seen your target for yourself, rather than depend upon someone else's description.

In reply to Re^2: Buffered IO and un-intended slurping by Wiggins
in thread Buffered IO and un-intended slurping by Wiggins

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