Girish

• Jul 23rd, 2005

 

Can any on tell me the resone for empty out put . I thught the the out put will be some garbage value . 
 
because malloc() desnot intialise any value. I had tryed this program and i got the answer empty string . then i cahnged the program like this... 
int main() 
{ 
abc(); 
ab(); 
return 0; 
} 
int abc() 
{ 
char *p1="Name"; 
char *p2="abcdefghidfsjlkdf"; 
free p2; 
return 0; 
} 
int ab() 
{ 
char *p1="Name"; 
char *p2; 
p2=(char *)malloc(20); 
while(*p2++=*p1++); 
printf("%sn",p2); 
} 
/* ther may be some sytax mistakes here , because i am writing here only */ 
 
in this i got some gurbage value . can any one explaine me a bit more on this...

harshita

• Aug 6th, 2005

 

Answer : An empty string 
The main aim of this prg is to copy string p1 into p2 . In the while loop we keep on incrementing p2 and p1 . By the end of while loop the pointer p2 is shifted by 5 . So it prints out an empty string.  
Try the following: 
#include 
int p; 
int main() 
{ 
 
char *p1="Name"; 
char *p2, *p3; 
p2=(char *)malloc(20); 
p3=p2; 
while(*p2++=*p1++); 
printf("n%s",(p2-5)); 
} 
 
It will print p2=Name