The standard C library, `libc.a', is automatically linked into your programs by the `gcc' control program. It provides many of the functions that are normally associated with C programs. This document gives the proper usage information about each of the functions and variables found in `libc.a'.
For each function or variable that the library provides, the definition of that symbol will include information on which header files to include in your source to obtain prototypes and type definitions relevent to the use of that symbol.
Note that many of the functions in `libm.a' (the math library) are
defined in `math.h' but are not present in libc.a. Some are, which
may get confusing, but the rule of thumb is this - the C library
contains those functions that ANSI dictates must exist, so that you
don't need the -lm if you only use ANSI functions. These
functions are, however, vastly simplified compared to the ANSI spec and
the functions in `libm.a', which includes replacements. For
example, libc.a's ldexp() doesn't set errno on
error, but libm.a's ldexp() does.
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