Hi folks, I've been looking at Unix v5 cc limitations. It seems like early cc could only use variable and function names up to 8 characters. This limitation occurs in v5, v6 and v7. But when using the nm utility to print out the name list I see function test1234() listed as: 000044T _test123 That seems to suggest that only the first 7 characters are significant, but when looking at other sources they stated that one can use up to 8 characters. I hacked up a short program to test this: main() { test1234(); test1235(); } test1234() { printf ("\nWorking"); } test1235() { printf ("\nAlso working"); } This generated: Multiply defined: test5.o;_test123 So it would seem that function names can only be 7 characters in length. I am not sure if limitations of early cc were documented anywhere. When I backported unirubik to v5 it compiled the longer functions without any problem. Did anyone document these sorts of limitations of early cc? Does anyone remember when cc started to use function names longer than 7 characters? Mark _______________________________________________ TUHS mailing list TUHS(a)minnie.tuhs.org https://minnie.tuhs.org/mailman/listinfo/tuhs

On Thu, 16 Oct 2014, Mark Longridge wrote: In those days it took only the first seven and ignored the rest, prepending an underscore as you discovered. I don't remember when longer names were recognised; for all I know it could've been around when pathnames could be longer than 14 chars (which I think may have been a BSDism).

> For VAX, 4BSD appears to use an "index into file string table", whereas > 3BSD still has an 8-character string. I don't see any provision in the > 4BSD linker for loading 3BSD binaries.

> Filenames over 14 characters appear to have been introduced in 4.1BSD.

Warner Losh <imp(a)bsdimp.com> wrote:

I think System III or System V picked this up. No, at 4.2 BSD with the Fast Filesystem. (Maybe 4.1c or some such already had the FFS, but the original 4.1 didn't...)