isprint() - ctype.h

The C library function int isprint(int c) checks whether the passed character is printable. A printable character is a character that is not a control character.
This function returns a non-zero value(true) if c is a printable character else, zero (false).

Syntax

int isprint(int c);

Example

#include <stdio.h>
#include <ctype.h>

int main()
{
   int var1 = 'k';
   int var2 = '8';
   int var3 = '\t';
   int var4 = ' ';
    
   if( isprint(var1) )
   {
      printf("var1 = |%c| can be printed\n", var1 );
   }
   else
   {
      printf("var1 = |%c| can't be printed\n", var1 );
   }
   
   if( isprint(var2) )
   {
      printf("var2 = |%c| can be printed\n", var2 );
   }
   else
   {
      printf("var2 = |%c| can't be printed\n", var2 );
   }
   
   if( isprint(var3) )
   {
      printf("var3 = |%c| can be printed\n", var3 );
   }
   else
   {
      printf("var3 = |%c| can't be printed\n", var3 );
   }
   
   if( isprint(var4) )
   {
      printf("var4 = |%c| can be printed\n", var4 );
   }
   else
   {
      printf("var4 = |%c| can't be printed\n", var4 );
   }
   
   return(0);
}

Output / Return Value

var1 = |k| can be printed                                                   
var2 = |8| can be printed                                                   
var3 = |        | can't be printed                                          
var4 = | | can be printed

Limitations

Alternatives / See Also

Reference