Programming :: Dereferencing Pointer To A Shared Memory Struct?
Feb 5, 2011
I have what should be a relatively simple program (fadec.c) that maps a struct from an included header file (fadec.h) to a shared memory region, but Im struggling accessing members in the struct from the pointer returned by shmat. Ultimately, I want to access members in the shared memory structure with a globally declared version of the struct, shm__. Not only do I not know how to accomplish that, but I cant even seem to access members of the shared struct directly from the pointer itself (compiler complains about dereferencing pointer to incomplete type). Im at a loss and could use another set of eyes if you guys dont mind taking a gander:
Compile Errors:
tony-pc:/cygdrive/p/test> cc -o fadec fadec.c
fadec.c: In function 'main':
fadec.c:30: error: dereferencing pointer to incomplete type
fadec.c:31: error: dereferencing pointer to incomplete type
[Code]...
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Sep 29, 2010
I have got following code from a book:
Code:
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <string.h>
#include <stdlib.h>
#define PORTNUMBER 12345
[Code]...
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May 15, 2011
I am playing around with a new chat program and I have errors that I can not figure out. Here is what I am getting.
parse.c:1638: error: dereferencing pointer to incomplete type
parse.c:1638: error: dereferencing pointer to incomplete type
parse.c:1638: error: dereferencing pointer to incomplete type
here is the code:
if (scan->jail_timeout == 0 && scan->location == prison)
{
command_type |= HIGHLIGHT;
tell_player(scan, " After serving your sentence you are flung out"
[code]....
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Code:
int main()
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[code].....
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it gives me an error---
In funtion 'int main()':
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Here is my code:
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Code:
#include <stdio.h>
#include <stdlib.h>
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[code]....
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Mar 17, 2010
So I'll try to be brief and to the point here: I've got a couple of C / C++ apps that communicate with one another via shared memory. These worked completely fine until.. well, about twenty minutes ago when I finished making some network card changes and suddenly, I've got a weird problem going on. At one point, Parent app waits for Child app to set a boolean indicating it's finished initialization. This worked fine the last time I ran this app up (a few days ago). But right now, the shared flag never seems to get triggered (I've added a printf("Waiting..."); in Parent app until the flag is set). All the code leading up to it being set in Child app seem to be running smoothly, so I tried spitting out the addresses of the shared memory locations. The addresses mapped by Parent app and Child app are different; this seemed odd, so I went back and wrote a simple miniature app that just opened a shared structure on my own box, and I get the same thing - different addresses - but the miniature apps work just fine.
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Code:
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