Craig A. Berry <[EMAIL PROTECTED]> writes: >At 05:54 PM 5/21/2002 +0100, Nick Ing-Simmons wrote: >>Nicholas Clark <[EMAIL PROTECTED]> writes: > >>>What do you mean multiple ungetc? >>>If that's going to stdio, ANSI only guarantee that the first ungetc will >>>succeed. >> >>I know that. ANSI C does not allow you to snoop the buffer either but we >>do that as well. It is also not unreasonable if buffer is snoopable to >>expect that we can "unget" back to begining of the buffer. > >Which will, if I'm understanding this, never be more than 1 byte on VMS. I >found in some release notes to a BIND server patch a bit more about this >than is readily available in the compiler or C library docs: > ><http://ftp1.support.compaq.com/patches/public/Readmes/vms/tcpipalp_e03a50.README> > >I'll quote the bit that seems most relevant: > >"The size of the pushback buffer for the DEC C RTL is 1, and once it is full >additional calls to ungetc() will fail.
Ah. But note though that the iperlsys.h stuff does some other hackery. Break-points in PerlStdio_unread() would be informative - if we ever get there then VMS is going to exercise paths that other stdio's have not pipe-cleaned. -- Nick Ing-Simmons http://www.ni-s.u-net.com/
