> Is it that the linker prefers a symbol from a .5 file over the .a file?
I believe it's supposed to pick the first one it finds. Object files and libraries are processed in the order in which they appear on the command line. On my system proc.5 appears before libc.a in the ld command, and libc.a(sleep.5) doesn't contain any symbols other than sleep, so there should be no reason for ld to pull it in from the library.
