Stdio.h 1. I can not find the definition of FILE data type as explained at opengroup.org: "A structure containing information about a file, defined through typedef." 2. I can not find where stdarg.h is so I assume that it is missing and so "va_list" is never defined. 3. Stddef.h is missing and size_t declaration and definition are missing. 4. Other things seems to be ok. There aren't undeclared functions in Haiku's stdio.h. There are even declarations of functions which are missing at opengroup.org. Math.h 1. Missing definition of float_t and double_t as described at opengroup.org. 2. Missing declaration of FLT_EVAL_METHOD. 3. Function "int isgreater(real-floating x, real-floating y);" is never defined or declared in the header. 4. Function "int isgreaterequal(real-floating x, real-floating y);" is never defined or declared in the header. 5. Functions "int isless(real-floating x, real-floating y);, int islessequal(real-floating x, real-floating y);, int islessgreater(real-floating x, real-floating y);" are never defined or declared in the header. 6. Function "int isunordered(real-floating x, real-floating y);" is never defined or declared in the header. 7. There is no definition of "MAXFLOAT" constant in the header. 8. The following optional macros “FP_FAST_FMA, FP_FAST_FMAF, FP_FAST_FMAL” are not defined in the header. 9. The following macros “FP_ILOGB0, FP_ILOGBNAN, MATH_ERRNO, MATH_ERREXCEPT, math_errhandling” are never defined in the header. nl_types.h 1. Everything seems to be OK. wchar.h 1. Can not find where stddef.h is. (where wchar_t is defined) 2. The tag "tm" is not declared as described at opengroup.org. wtype.h 1. The macro "WEOF" is not defined as described at opengroup.org stdlib.h 1. Definition of "NULL" is missing. (It is posible to be in stddef.h) 2. "" seems not to be included, so "WNOHANG WUNTRACED WEXITSTATUS WIFEXITED WIFSIGNALED WIFSTOPPED WSTOPSIG WTERMSIG" definition is missing. 3. Definition/Declaration of "long a64l(const char *);" seems to be missing. 4. Definition/Declaration of "int atexit(void (*)(void));" seems to be missing. 5. Definition/Declaration of "div_t div(int, int);" seems to be missing. 6. Definition/Declaration of "char* l64a(long);" seems to be missing. search.h 1. Everything seems to be OK.