- Fix the claim that the output is always null-terminated. This isn't   true if the size is zero. - Fix a claim that sprintf() is the same as snprintf() with an   infinite size.  It's equivalent to snprintf() with a size of   INT_MAX + 1. - Document the return values in the return values section. - Document the possible errno value of EOVERFLOW.
- Fix the claim that the output is always null-terminated. This isn't
  true if the size is zero.
- Fix a claim that sprintf() is the same as snprintf() with an
  infinite size.  It's equivalent to snprintf() with a size of
  INT_MAX + 1.
- Document the return values in the return values section.
- Document the possible errno value of EOVERFLOW.

MFC after:	2 weeks

jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase,jrobhoward/SCADAbase