Table 3-1 describes the character, string, and argument-list functions in the DEC C Run-Time Library (RTL). Although further discussion follows, see the Reference Section for more detailed information on each function.
| Function | Description |
|---|---|
| Character Classification | |
| isalnum, iswalnum | Returns a nonzero integer if its argument is one of the alphanumeric characters in the current locale. |
| isalpha, iswalpha | Returns a nonzero integer if its argument is one of the alphabetic characters in the current locale. |
| isascii | Returns a nonzero integer if its argument is any ASCII character. |
| iscntrl, iswcntrl | Returns a nonzero integer if its argument is a control character in the current locale. |
| isdigit, iswdigit | Returns a nonzero integer if its argument is a digit character in the current locale. |
| isgraph, iswgraph | Returns a nonzero integer if its argument is a graphic character in the current locale. |
| islower, iswlower | Returns a nonzero integer if its argument is a lowercase character in the current locale. |
| isprint, iswprint | Returns a nonzero integer if its argument is a printing character in the current locale. |
| ispunct, iswpunct | Returns a nonzero integer if its argument is a punctuation character in the current locale. |
| isspace, iswspace | Returns a nonzero integer if its argument is a white space character in the current locale. |
| isupper, iswupper | Returns a nonzero integer if its argument is an uppercase character in the current locale. |
| isxdigit, iswxdigit | Returns a nonzero integer if its argument is a hexadecimal digit (0 to 9, A to F, or a to f). |
| Character Conversion | |
| btowc | Converts a one-byte multibyte character to a wide character in the initial shift state. |
| ecvt, fcvt, gcvt | Converts an argument to a null-terminated string of ASCII digits and return the address of the string. |
| index, rindex | Searches for a character in a string. |
| mblen, mbrlen | Determines the number of bytes in a multibyte character. |
| mbsinit | Determines whether an mbstate_t object decribes an initial conversion state. |
| mbstowcs | Converts a sequence of multibyte characters into a sequence of corresponding codes. |
| toascii | Converts its argument, an 8-bit ASCII character, to a 7-bit ASCII character. |
| tolower, _tolower, towlower | Converts its argument, an uppercase character, to lowercase. |
| toupper, _toupper, towupper | Converts its argument, a lowercase character, to uppercase. |
| towctrans | Maps one wide character to another according to a specified mapping descriptor. |
| wctob | Determines if a wide character corresponds to a single-byte multibyte character and returns its multibyte character representation. |
| wcstombs | Converts a sequence of wide-character codes corresponding to multibyte characters to a sequence of multibyte characters. |
| wctomb | Converts a wide character to its multibyte character representation. |
| wctrans | Returns the description of a mapping, corresponding to specified property, that can be later used in a call to towctrans. |
| String Manipulation | |
| atof | Converts a given string to a double-precision number. |
| atoi, atol | Converts a given string of ASCII characters to the appropriate numeric values. |
| atoll, atoq (Alpha only) | Converts a given string of ASCII characters to an __int64. |
| basename | Returns the last component of a path name. |
| dirname | Reports the parent directory name of a file path name. |
| strcat, strncat, wcscat, wcsncat | Appends one string to the end of another string. |
| strchr, strrchr, wcschr, wcsrchr | Returns the address of the first or last occurrence of a given character in a null-terminated string. |
| strcmp, strncmp, strcoll, wcscmp, wcsncmp, wcscoll | Compares two character strings and return a negative, zero, or positive integer indicating that the values of the individual characters in the first string are less than, equal to, or greater than the values in the second string. |
| strcpy, strncpy, wcscpy, wcsncpy | Copies all or part of one string into another. |
| strxfrm, wcsxfrm | Transforms a multibyte string to another string ready for comparisons using the strcmp or wcscmp function. |
| strcspn, wcscspn | Searches a string for a character that is in a specified set of characters. |
| strlen, wcslen | Returns the length of a string of characters. The returned length does not include the terminating null character (\0). |
| strpbrk, wcspbrk | Searches a string for the occurrence of one of a specified set of characters. |
| strspn, wcsspn | Searches a string for the occurrence of a character that is not in a specified set of characters. |
| strstr, wcswcs | Searches a string for the first occurrence of a specified set of characters. |
| strtod, wcstod | Converts a given string to a double-precision number. |
| strtok, wcstok | Locates text tokens in a given string. |
| strtol, wcstol | Converts the initial portion of a string to a signed long integer. |
| strtoll, strtoq (Alpha only) | Converts the initial portion of a string to signed __int64. |
| strtoul, wcstoul | Converts the initial portion of `a string to an unsigned long integer. |
| strtoull, strtouq (Alpha only) | Converts the initial portion of the string pointed to by the pointer to the character string to an unsigned __int64. |
| String Handling-Accessing Binary Data | |
| bcmp | Compares byte strings. |
| bcopy | Copies byte strings. |
| bzero | Copies nulls into byte strings. |
| memchr, wmemchr | Locates the first occurrence of the specified byte within the initial length of the object to be searched. |
| memcmp, wmemcmp | Compares two objects byte by byte. |
| memcpy, memmove, wmemcpy, wmemmove | Copies a specified number of bytes from one object to another. |
| memset, wmemset | Sets a specified number of bytes in a given object to a given value. |
| Argument-List Handling- Accessing a Variable-Length Argument List | |
| va_arg | Returns the next item in the argument list. |
| va_count | Returns the number of longwords (VAX only) or quadwords (VAX only) in the argument list. |
| va_end | Finishes the va_start session. |
| va_ start, va_start_1 | Initializes a variable to the beginning of the argument list. |
| vfprintf, vprintf, vsprintf | Prints formatted output based on an argument list. |