Difference between C standard library and C POSIX library

Question

I\'m a little confused by \"C standard lib\" and \"C POSIX lib\", because I found that, many header files defined in \"C POSIX lib\" are also part of \"C standard lib\".

Answer 1

The C POSIX library is a specification of a C standard library for POSIX systems. It was developed at the same time as the ANSI C standard. Some effort was made to make POSIX compatible with standard C; POSIX includes additional functions to those introduced in standard C.