VAX VMS C / UNIX C Compatibility -- Need Info

eric stern at bnl.UUCP
Wed Aug 28 02:50:32 AEST 1985


> > VMS is very record-ish, while stream i/o is the unix thing. Unfortunately,
> > port didn't work because we didn't really spend the effort required to do
> > the QIO's required to fake stream i/o on VMS. 
> 

A year or two ago, I wrote a xmodem protocol program for VMS and
UNIX in C.  The effort required to set up the raw state in both OS's
was equivalent.  Doing these things on VMS takes no more effort
than finding the appropriate ioctl function codes on UNIX.  When
it got to doing the reads byte by byte with timeouts, VMS was
much simpler than UNIX.  Under VMS, just one function call was
able to read n characters returning an error if more than t
seconds elapsed between characters.  Under UNIX, it was a complicated
mess with two functions, alarms, longjmps and extra buffering.

						Eric G. Stern
						stern at bnl.arpa
						stern at bnl.bitnet
						...!philabs!sbcs!bnl!stern



More information about the Comp.lang.c mailing list