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isalnum()

Syntax:

#include <ctype.h>
int isalnum( int ch );

Description:
The function isalnum() returns non-zero if its argument is a numeric digit or a letter of the alphabet. Otherwise, zero is returned.

Example:

char c;
scanf( "%c", &c );
if( isalnum(c) )
  printf( "You entered the alphanumeric character %c\n", c );

Related Topics:
isalpha(), iscntrl(), isdigit(), isgraph(), isprint(), ispunct(), isspace()

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