C library - iswgraph() function

The C wctype library iswgraph() function is used to check if a given wide character (of type wint_t) is a graphical character. Graphical characters include all printable characters except space.

The printable character includes either a number (0123456789), an uppercase letter (ABCDEFGHIJKLMNOPQRSTUVWXYZ), a lowercase letter (abcdefghijklmnopqrstuvwxyz), a punctuation character (!"#$%&'()*+,-./:;?@[\]^_`{|}~) or any graphical character specific to the current C locale.

Syntax

Following is the C library syntax of iswgraph() function −

int iswgraph( wint_t ch );

Parameters

This function accepts a single parameter −

• ch − It is a wide character of type 'wint_t' to be checked.

Return Value

This function returns Non-zero value if the wide character has a graphical representation character, zero otherwise.

Example 1

The following is the basic c example that demonstrate the use of iswgraph() to identify graphical characters in a wide character set.

#include <locale.h>
#include <stdio.h>
#include <wchar.h>
#include <wctype.h>

int main(void) {
   // "en_US.utf8" to handle Unicode characters
   setlocale(LC_ALL, "en_US.utf8");

   // Array of wide characters including
   wchar_t character[] = {L'A', L' ', L'\n', L'\u2028'};
   
   size_t num_char = sizeof(character) / sizeof(character[0]);

   // Check and print if a character is graphical character or not
   printf("Checking graphical characters:\n");
   for (size_t i = 0; i < num_char; ++i) {
      wchar_t ch = character[i];
      printf("Character '%lc' (%#x) is %s graphical char\n", ch, ch, iswprint(ch) ? "a" : "not a");
   }
   
   return 0;
}

Output

Following is the output −

Checking graphical characters:
Character 'A' (0x41) is a graphical character
Character ' ' (0x20) is a graphical character
Character '
' (0xa) is not a graphical character
Character ' ' (0x2028) is not a graphical character

Example 2

Let's create another c program and use the iswgraph() to the check if the special character is a graphical character or not in the Unicode locale.

#include <locale.h>
#include <stdio.h>
#include <wchar.h>
#include <wctype.h>

int main(void) {
   // "en_US.utf8" to handle Unicode characters
   setlocale(LC_ALL, "en_US.utf8");

   wchar_t spclChar[] = {L'@', L'#', L'$', L'%'};
   
   size_t num_char = sizeof(spclChar) / sizeof(spclChar[0]);

   // Check and print if a character is graphical character or not
   printf("Checking graphical characters:\n");
   for (size_t i = 0; i < num_char; ++i) {
      wchar_t ch = spclChar[i];
      printf("Char '%lc' (%#x) is %s graphical char\n", ch, ch, iswprint(ch) ? "a" : "not a");
   }
   
   return 0;
}

Output

Following is the output −

Checking graphical characters:
Char '@' (0x40) is a graphical char
Char '#' (0x23) is a graphical char
Char '$' (0x24) is a graphical char
Char '%' (0x25) is a graphical char