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help with string slicing in C

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Top Forums Programming help with string slicing in C
# 8  
Old 04-06-2011
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Quote:
Originally Posted by omega666
wouldnt this work, since strings are pointers?
buf=buf+5;

and whats the difference between declaring a string like
char *buf;
and
char buf[10];

arent they both pointers? But in some cases the way i declare it makes a difference through...
Strings are NOT pointers. Pointer airthmetic (buf = buf + 5) can only be applied if buf is a pointer (char *buf) and not if it is a string (char buf [20] ) . If you want to do pointer airthmetic on a string, get a pointer to point to the base of the string and perform pointer airthmetic on the "pointer".

Code:
char buf [20]; //string 

char *pointer_to_buf = buf   // char pointer to the base of 
                                                // string "buf" 
pointer_to_buf += 5;  // gets the pointer to point to the 
                                     // address of buf [4]

Read K&R (Pointers and Arrays - chapter 5)

Thanks,
Gaurav.
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