Here's a regular expression to match stdlib types and subroutines to add stdlib
highlighting to C, C++, and Yacc pattern sets (from Philippe Couton):

   <(BUFSIZ|CHAR_BIT|CHAR_MAX|CHAR_MIN|CLOCKS_PER_SEC|DBL_DIG|DBL_EPSILON|DBL_MANT_DIG|DBL_MAX|DBL_MAX_10_EXP|DBL_MAX_EXP|DBL_MIN|DBL_MIN_10_EXP|DBL_MIN_EXP|EDOM|EOF|ERANGE|EXIT_FAILURE|EXIT_SUCCESS|FILE|FILENAME_MAX|FLT_DIG|FLT_EPSILON|FLT_MANT_DIG|FLT_MAX|FLT_MAX_10_EXP|FLT_MAX_EXP|FLT_MIN|FLT_MIN_10_EXP|FLT_MIN_EXP|FLT_RADIX|FLT_ROUNDS|FOPEN_MAX|HUGE_VAL|INT_MAX|INT_MIN|LC_ALL|LC_COLLATE|LC_CTYPE|LC_MONETARY|LC_NUMERIC|LC_TIME|LDBL_DIG|LDBL_EPSILON|LDBL_MANT_DIG|LDBL_MAX|LDBL_MAX_10_EXP|LDBL_MAX_EXP|LDBL_MIN|LDBL_MIN_10_EXP|LDBL_MIN_EXP|LONG_MAX|LONG_MIN|L_tmpnam|MB_CUR_MAX|MB_LEN_MAX|NULL|RAND_MAX|SCHAR_MAX|SCHAR_MIN|SEEK_CUR|SEEK_END|SEEK_SET|SHRT_MAX|SHRT_MIN|SIGABRT|SIGFPE|SIGILL|SIGINT|SIGSEGV|SIGTERM|SIG_DFL|SIG_ERR|SIG_IGN|TMP_MAX|UCHAR_MAX|UINT_MAX|ULONG_MAX|USHRT_MAX|WCHAR_MAX|WCHAR_MIN|WEOF|_IOFBF|_IOLBF|_IONBF|abort|abs|acos|asctime|asin|assert|atan|atan2|atexit|atof|atoi|atol|bsearch|btowc|calloc|ceil|clearerr|clock|clock_t|cos|cosh|ctime|difftime|div|div_t|errno|exit|exp|fabs|fclose|feof|ferror|fflush|fgetc|fgetpos|fgets|fgetwc|fgetws|floor|fmod|fopen|fpos_t|fprintf|fputc|fputs|fputwc|fputws|fread|free|freopen|frexp|fscanf|fseek|fsetpos|ftell|fwide|fwprintf|fwrite|fwscanf|getc|getchar|getenv|gets|getwc|getwchar|gmtime|isalnum|isalpha|iscntrl|isdigit|isgraph|islower|isprint|ispunct|isspace|isupper|iswalnum|iswalpha|iswcntrl|iswctype|iswdigit|iswgraph|iswlower|iswprint|iswpunct|iswspace|iswupper|iswxdigit|isxdigit|jmp_buf|labs|lconv|ldexp|ldiv|ldiv_t|localeconv|localtime|log|log10|longjmp|malloc|mblen|mbrlen|mbrtowc|mbsinit|mbsrtowcs|mbstate_t|mbstowcs|mbtowc|memchr|memcmp|memcpy|memmove|memset|mktime|modf|offsetof|perror|pow|printf|ptrdiff_t|putc|puts|putwc|putwchar|qsort|raise|rand|realloc|remove|rename|rewind|scanf|setbuf|setjmp|setlocale|setvbuf|sig_atomic_t|signal|sin|sinh|size_t|sprintf|sqrt|srand|sscanf|stderr|stdin|stdout|strcat|strchr|strcmp|strcoll|strcpy|strcspn|strerror|strftime|strlen|strncat|strncmp|strncpy|stroul|strpbrk|strrchr|strspn|strstr|strtod|strtok|strtol|strxfrm|swprintf|swscanf|system|tan|tanh|time|time_t|tm|tmpfile|tmpnam|tolower|toupper|towctrans|towlower|towupper|ungetc|ungetwc|va_arg|va_end|va_list|va_start|vfwprintf|vprintf|vsprintf|vswprintf|vwprintf|wint_t|wmemchr|wmemcmp|wmemcpy|wmemmove|wmemset|wprintf|wscanf)>