Listing 1

 2  //    ** nonprtsh.c ** Program to show certain non print characters
 3  //    Based on algorithm by Dr P.J.Plauger CUJ oct 1990 p130
 
 5  #include <stdio.h>
 6  #include <conio.h>
 7  #include <string.h>
 
 9  void printxxx(int c);
10
11  void main(void)
12  {
13      int a=0x0;
14
15      while(a!=0x2a) // end program if * entered
16           {
17           printf("\nEnter character:");
18           a=getch();
19           printxxx(a);
20           }
21  }
2Z
23  void printxxx(int c!)
24  {
25          static char esc[]="\a\b\t\n\r\x1a\x1b";
26          static char prt[]="BEL\OBS \OHT \OLF \OCR \OSUB\OESC";
27          char *s=strchr(esc,c);
28          if(s)
Zf               printf("[%s]",prt+4*(s-esc));
30          else
31               printf("%c",c);
32  }