Login or Register to Ask a Question and Join Our Community

Sponsored Content
Full Discussion: pointer problem
Top Forums Programming pointer problem Post 302144406 by porter on Thursday 8th of November 2007 01:24:23 AM
Old 11-08-2007
Code:
/usr/local/bin/gcc -Wall -Werror ptr.c -o ptr
ptr.c:4: warning: return type defaults to `int'
ptr.c: In function `main':
ptr.c:7: warning: missing braces around initializer
ptr.c:7: warning: (near initialization for `a[0]')
ptr.c:13: warning: assignment from incompatible pointer type

Try compiling with full warnings. They actually help.

Multi-dimensional arrays are a bit tricky in C.

Code:
#include<stdio.h>

int main(int argc,char **argv)
{
    int a[3][3]={
        {1,2,5},
        {4,5,6},
        {8,9,0}
    };
    typedef int slice[3];
    slice *ptr;

    ptr=a;

    printf("%d\n" , **ptr);

    return 0;
}

 

10 More Discussions You Might Find Interesting

1. Programming

Problem with function which reutrns pointer to a value

i have a function: char *pcCityIdToCountryName(ADMIN_DB_DATA *pstHEader, unit uiCityID) this returns a pointer to CountryName if cityId is given. to retrieve countryname i give: char *CountryName; CountryName = pcCityIdToCountryName(..................); but when i compile it is giving :... (5 Replies)
Discussion started by: jazz
5 Replies

2. Programming

pointer

void main() { int a={1,2,3,4,5,6,7,8,9,10}; int *p=a; int *q=&a; cout<<q-p+1<<endl; } The output is 10, how? if we give cout<<q it will print the address, value won't print.... if we give cout<<p it will print the address, value won't print.... p has the base addr; q... (1 Reply)
Discussion started by: sarwan
1 Replies

3. Programming

why we never delete a pointer twice

can u tell me the reson that why we should not delete a pointer twice.? if we delete ponter twice then what happen and why this happen Regards, Amit (2 Replies)
Discussion started by: amitpansuria
2 Replies

4. Programming

far pointer

what is far pointer in C (1 Reply)
Discussion started by: useless79
1 Replies

5. Programming

String and pointer problem

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 "X1 " ---> string lenght is 15... (3 Replies)
Discussion started by: arunkumar_mca
3 Replies

6. Programming

Need help in character pointer

Hi, I am trying to divide my input to different type of out puts for some other use. ex: logical_name : jkl00001 expected out put : model=jkl and num=00001 here is the code i actually written /*******************************************************************/ void... (11 Replies)
Discussion started by: jagan_kalluri
11 Replies

7. Programming

pass a pointer-to-pointer, or return a pointer?

If one wants to get a start address of a array or a string or a block of memory via a function, there are at least two methods to achieve it: (1) one is to pass a pointer-to-pointer parameter, like: int my_malloc(int size, char **pmem) { *pmem=(char *)malloc(size); if(*pmem==NULL)... (11 Replies)
Discussion started by: aaronwong
11 Replies

8. Programming

unidirectional linked list pointer problem

I am trying to test some operations on a directed list. However, the declaration of a pointer is giving me trouble. I seem to have done something incorrectly because I get an error: "listtest.c:29: warning: 'p' may be used uninitialized in this function" Can anyone help? This is my code... (6 Replies)
Discussion started by: bluetxxth
6 Replies

9. Programming

pointer problem

Does anyone know? int x = 1; int *p = &++x; //ok ! int *q = &x++; //gives an error :O why the first pointer is ok but the second is an error? (13 Replies)
Discussion started by: nishrestha
13 Replies

10. Programming

Scanf() string pointer problem

I have a problem with scanf() for string pointer as member of a struct. #include <stdio.h> #include <stdlib.h> struct Student { int studentNumber; int phoneNumber; char *studentName; //line 7 // char studentName; //line 8 }; int... (10 Replies)
Discussion started by: yifangt
10 Replies

LEARN ABOUT NETBSD

atomic_dec_uint

ATOMIC_DEC(3)						   BSD Library Functions Manual 					     ATOMIC_DEC(3)

NAME

     atomic_dec, atomic_dec_32, atomic_dec_uint, atomic_dec_ulong, atomic_dec_ptr, atomic_dec_64, atomic_dec_32_nv, atomic_dec_uint_nv,
     atomic_dec_ulong_nv, atomic_dec_ptr_nv, atomic_dec_64_nv -- atomic decrement operations

SYNOPSIS

     #include <sys/atomic.h>

     void
     atomic_dec_32(volatile uint32_t *ptr);

     void
     atomic_dec_uint(volatile unsigned int *ptr);

     void
     atomic_dec_ulong(volatile unsigned long *ptr);

     void
     atomic_dec_ptr(volatile void *ptr);

     void
     atomic_dec_64(volatile uint64_t *ptr);

     uint32_t
     atomic_dec_32_nv(volatile uint32_t *ptr);

     unsigned int
     atomic_dec_uint_nv(volatile unsigned int *ptr);

     unsigned long
     atomic_dec_ulong_nv(volatile unsigned long *ptr);

     void *
     atomic_dec_ptr_nv(volatile void *ptr);

     uint64_t
     atomic_dec_64_nv(volatile uint64_t *ptr);

DESCRIPTION

     The atomic_dec family of functions decrement (by one) the variable referenced by ptr in an atomic fashion.

     The *_nv() variants of these functions return the new value.

     The 64-bit variants of these functions are available only on platforms that can support atomic 64-bit memory access.  Applications can check
     for the availability of 64-bit atomic memory operations by testing if the pre-processor macro __HAVE_ATOMIC64_OPS is defined.

SEE ALSO

     atomic_ops(3)

HISTORY

     The atomic_dec functions first appeared in NetBSD 5.0.

BSD
								  April 11, 2007							       BSD
All times are GMT -4. The time now is 10:13 PM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy