[Info-vax] net: device (Re: C compiler snag)

[Craig A. Berry]

On 5/21/21 12:42 PM, Simon Clubley wrote:
> There is a problem when you use net/
> within an include statement. The following code compiles: !!!
> 
> ---------------------------------------------------------------------------
> $ type nettest.c
> #include <stdio.h>
> #include <net/does_not_exist.h>
> 
> int main(int argc, char *argv[])
>          {
>          printf("Testing net include\n");
>          return 0;
>          }
> $ cc nettest.c
> ---------------------------------------------------------------------------

Bug or feature I don't know, but again it seems to have nothing to do
with the compiler.  Opening a non-existent file on the net: device
returns success.  What you expect from opening a non-existent file:

$ perl -e "open my $f, '<', 'nosuchfile.dat' or die $^E;"
%RMS-E-FNF, file not found at -e line 1.
%SYSTEM-F-ABORT, abort

What you get when you prepend "net:" to the filename:

$ perl -e "open my $f, '<', 'net:nosuchfile.dat' or die $^E;"
$ show symbol $status
   $STATUS == "%X00000001"

Note that you can't reproduce this with DCL:

$ open f net:nosuchfile.dat
%DCL-E-INVRFM, invalid record format for record I/O - file not opened

So the compiler is just converting net/does_not_exist.h to VMS syntax
net:does_not_exist.h and getting a successful open but nothing happens
when you read from it (except EOF I guess).  The filename portion
doesn't matter and seems to be ignored.  As far as I can tell, the
behavior is identical to that of _NLA0:.

The compiler could also be led astray by:

#include "nl/foo.h"