0

Hello guys.
Can I write structure data to child pipe?
Usual examples are about writing char* or int type.
I tried to write structure. But it does not look work.
Will you check my code?
-----------------------------------------------------------------------

struct work_list {
	int heavy_rate; //0 - 5 level
	int work_owner; //thread id
} ; 

int main(void)
{
int     fd[2], nbytes, icount;
pid_t   childpid;

work_list work_ll[5] = {
	{3, 5}, {3, 3}, {3, 4}, {4, 1}, {4, 3}};

work_list *readbuffer;
pipe(fd);
    
if((childpid = fork()) == -1)
   {
	perror("fork");
   }

if(childpid != 0)
   {
	close(fd[0]);
	write(fd[1], work_ll, (sizeof(work_ll)+1));
   }
else
   {
	close(fd[1]);
	nbytes = read(fd[0], readbuffer, sizeof(readbuffer));
	cout << "Received string: " << readbuffer[0].dirty_rate << " byte " << nbytes << endl;
   }
}
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Last Post by nezachem
0

where did you call popen() to open the pipe?

[edit]Oh never mind. I checked the *nix man page and it appears you did it the same way as in the example. Since I don't use *nix very often I have no clue what is wrong. [/edit]

Edited by Ancient Dragon: n/a

1

Writing (line 25) is almost OK (I think that a "+1" was added in an act of desperation, it is not needed there).
Reading (line 30) is a problem. First, a readbuffer is not initialized, so the segfault is imminent. Second, you only reading 4 bytes of the message. Fix those and we can proceed further.

To answer your original question, yes you can. You just need to be careful.

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