hello all,
my question is not about How code can be rewritten, i just wanna know even though i am not using read only memory of C (i have declared str[20]) why this function gives me segfault and the other code executes comfortably though both code uses same pointer arithmetic.
Code:
#include<stdio.h>
#include<string.h>
void reverse(char*);
int
main()
{
char str[20];
scanf("%s",str);
printf("original string is %s :\n",str);
reverse(str);
printf("reverse string is %s :",str);
return 0;
}
void reverse(char* s)
{
int n,mark,temp;
n = mark = strlen(s);
for(;s < (s + n/2);++s)
{
temp = *s;
*s = *(s + (--mark));
*(s + mark) = temp;
}
return;
}
i am having a string like
" X1 " ---> string lenght is 30
I have stored this to a chararry . ref
so here ref = " X1 "
now i trim the left space by my function . Si the string now becomes
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09-16-2011
and the other code executes comfortably though both code uses same pointer arithmetic.