.TH "ctype" 3avr "Fri Nov 24 2023 23:59:10" "Version 2.0.0" "avr-libc" \" -*- nroff -*- .ad l .nh .SH NAME ctype \- : Character Operations .SH SYNOPSIS .br .PP .SS "Character classification routines" These functions perform character classification\&. They return true or false status depending whether the character passed to the function falls into the function's classification (i\&.e\&. \fBisdigit()\fP returns true if its argument is any value '0' though '9', inclusive)\&. If the input is not an unsigned char value, all of this function return false\&. .in +1c .ti -1c .RI "int \fBisalnum\fP (int __c)" .br .ti -1c .RI "int \fBisalpha\fP (int __c)" .br .ti -1c .RI "int \fBisascii\fP (int __c)" .br .ti -1c .RI "int \fBisblank\fP (int __c)" .br .ti -1c .RI "int \fBiscntrl\fP (int __c)" .br .ti -1c .RI "int \fBisdigit\fP (int __c)" .br .ti -1c .RI "int \fBisgraph\fP (int __c)" .br .ti -1c .RI "int \fBislower\fP (int __c)" .br .ti -1c .RI "int \fBisprint\fP (int __c)" .br .ti -1c .RI "int \fBispunct\fP (int __c)" .br .ti -1c .RI "int \fBisspace\fP (int __c)" .br .ti -1c .RI "int \fBisupper\fP (int __c)" .br .ti -1c .RI "int \fBisxdigit\fP (int __c)" .br .in -1c .SS "Character convertion routines" This realization permits all possible values of integer argument\&. The \fBtoascii()\fP function clears all highest bits\&. The \fBtolower()\fP and \fBtoupper()\fP functions return an input argument as is, if it is not an unsigned char value\&. .in +1c .ti -1c .RI "int \fBtoascii\fP (int __c)" .br .ti -1c .RI "int \fBtolower\fP (int __c)" .br .ti -1c .RI "int \fBtoupper\fP (int __c)" .br .in -1c .SH "Detailed Description" .PP These functions perform various operations on characters\&. .PP .PP .nf #include .fi .PP .SH "Function Documentation" .PP .SS "int isalnum (int __c)\fC [extern]\fP" Checks for an alphanumeric character\&. It is equivalent to \fC(isalpha(c) || isdigit(c))\fP\&. .SS "int isalpha (int __c)\fC [extern]\fP" Checks for an alphabetic character\&. It is equivalent to \fC(isupper(c) || islower(c))\fP\&. .SS "int isascii (int __c)\fC [extern]\fP" Checks whether \fCc\fP is a 7-bit unsigned char value that fits into the ASCII character set\&. .SS "int isblank (int __c)\fC [extern]\fP" Checks for a blank character, that is, a space or a tab\&. .SS "int iscntrl (int __c)\fC [extern]\fP" Checks for a control character\&. .SS "int isdigit (int __c)\fC [extern]\fP" Checks for a digit (0 through 9)\&. .SS "int isgraph (int __c)\fC [extern]\fP" Checks for any printable character except space\&. .SS "int islower (int __c)\fC [extern]\fP" Checks for a lower-case character\&. .SS "int isprint (int __c)\fC [extern]\fP" Checks for any printable character including space\&. .SS "int ispunct (int __c)\fC [extern]\fP" Checks for any printable character which is not a space or an alphanumeric character\&. .SS "int isspace (int __c)\fC [extern]\fP" Checks for white-space characters\&. For the avr-libc library, these are: space, form-feed ('\\f'), newline ('\\n'), carriage return ('\\r'), horizontal tab ('\\t'), and vertical tab ('\\v')\&. .SS "int isupper (int __c)\fC [extern]\fP" Checks for an uppercase letter\&. .SS "int isxdigit (int __c)\fC [extern]\fP" Checks for a hexadecimal digits, i\&.e\&. one of 0 1 2 3 4 5 6 7 8 9 a b c d e f A B C D E F\&. .SS "int toascii (int __c)\fC [extern]\fP" Converts \fCc\fP to a 7-bit unsigned char value that fits into the ASCII character set, by clearing the high-order bits\&. .PP \fBWarning\fP .RS 4 Many people will be unhappy if you use this function\&. This function will convert accented letters into random characters\&. .RE .PP .SS "int tolower (int __c)\fC [extern]\fP" Converts the letter \fCc\fP to lower case, if possible\&. .SS "int toupper (int __c)\fC [extern]\fP" Converts the letter \fCc\fP to upper case, if possible\&. .SH "Author" .PP Generated automatically by Doxygen for avr-libc from the source code\&.