isalnum(3) [ultrix man page]
ctype(3) Library Functions Manual ctype(3) Name isalpha, isupper, islower, isdigit, isxdigit, isalnum, isspace, ispunct, isprint, isgraph, iscntrl, isascii - character classification macros Syntax #include <ctype.h> int isalpha (c) int c; Description These macros classify character-coded integer values according to the rules of the coded character set (codeset) identified by the last successful call to category All macros return non-zero for true and zero for false. If category has not been called successfully, or if character classification information is not available for a supported language, then characters are classified according to the rules of the ASCII 7-bit coded character set, returning 0 for values above octal 0177. The macro provides a result for all integer values. The rest provide a result for EOF and values in the character range of the codeset identified by the last successful call to category c is a letter c is an uppercase letter c is a lowercase letter c is a digit c is a hexadecimal digit, by default [0-9], [A-F], or [a-f] c is an alphanumeric character c is a space, tab, carriage return, new line, or form feed c is a punctuation character (neither control, alphanumeric, nor space) c is a printing character, by default code 040(8) (space) through 0176 (tilde) c is a printing character, like except false for space c is a delete character(0177) or ordinary control character (less than 040) except for space characters c is an ASCII character, code less than 0200 International Environment LC_CTYPE If this environment variable is set and valid, uses the international language database named in the definition to determine character classification rules. LANG If this environment variable is set and valid, uses the international language database named in the definition to determine the character classification rules. If is defined, that definition supercedes the definition of See Also conv(3), setlocale(3), stdio(3s), environ(5int), ascii(7) Guide to Developing International Software ctype(3)
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ctype(3) Library Functions Manual ctype(3) Name isalpha, isupper, islower, isdigit, isxdigit, isalnum, isspace, ispunct, isprint, isgraph, iscntrl, isascii - character classification macros Syntax #include <ctype.h> int isalpha (c) int c; Description These macros classify character-coded integer values according to the rules of the coded character set (codeset) identified by the last successful call to category All macros return non-zero for true and zero for false. If category has not been called successfully, or if character classification information is not available for a supported language, then characters are classified according to the rules of the ASCII 7-bit coded character set, returning 0 for values above octal 0177. The macro provides a result for all integer values. The rest provide a result for EOF and values in the character range of the codeset identified by the last successful call to category c is a letter c is an uppercase letter c is a lowercase letter c is a digit c is a hexadecimal digit, by default [0-9], [A-F], or [a-f] c is an alphanumeric character c is a space, tab, carriage return, new line, or form feed c is a punctuation character (neither control, alphanumeric, nor space) c is a printing character, by default code 040(8) (space) through 0176 (tilde) c is a printing character, like except false for space c is a delete character(0177) or ordinary control character (less than 040) except for space characters c is an ASCII character, code less than 0200 International Environment LC_CTYPE If this environment variable is set and valid, uses the international language database named in the definition to determine character classification rules. LANG If this environment variable is set and valid, uses the international language database named in the definition to determine the character classification rules. If is defined, that definition supercedes the definition of See Also conv(3), setlocale(3), stdio(3s), environ(5int), ascii(7) Guide to Developing International Software ctype(3)