UNIX C Pragma Directive

[David Lau]

I'm running AT&T UNIX System V, version 3.1?.  The developer's
package includes some .h files which hold #pragma directives, in
particular

#pragma pack(1)
...
#pragma

When I try to compile including any one of these .h files, I get an
"unknown syntax"-type of error.  Would someone tell me how I can get
my code to compile, whether through some flag or another means?

Thanks.