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Old 12-06-2010, 04:33 AM   #1
SuchANewb
LQ Newbie
 
Registered: Nov 2010
Posts: 7

Rep: Reputation: 0
Pipes problem


I am having a nightmare with this program. When I run it through a test it says following:

Error:
valgrind has detected an error in the program

==22165== Syscall param write(buf) points to uninitialised byte(s)
==22165== at 0x4EE5930: write (in /lib/libc-2.5.so)
==22165== by 0x400B4E: main (in /home/vajeacc/npipe)
==22165== Address 0x7FF000434 is on thread 1's stack
==22169== Syscall param write(buf) points to uninitialised byte(s)
==22169== at 0x4EE5930: write (in /lib/libc-2.5.so)
==22169== by 0x400CA4: main (in /home/vajeacc/npipe)
==22169== Address 0x7FF000434 is on thread 1's stack

Code:
    #include <sys/types.h>
    #include <sys/wait.h>
    #include <unistd.h>
    #include <stdlib.h>
    #include <stdio.h>

    int main(int argc, char** argv) 
    { 
		char temp_in[16]="";
		char temp_out[50][16];
		int pipa[2];
		int pipa2[2];
		int pipa3[2];
		int prices[50];
		int price = 0;
		int i = 0;
		pid_t pid;
		
		if (argc==1)
		{
			printf("Add an element!\n");
		}

		else
		{
			int products=argc-1;
	
			if(pipe(pipa) == -1)
			{ 
				perror("pipe call error");
				_exit(1);
			}
			if(pipe(pipa2) == -1) 
			{ 
				perror("pipe call error");
				_exit(1);
			}
			if(pipe(pipa2) == -1)
			{ 
				perror("pipe call error");
				_exit(1);
			}
			pid=fork();
          
			if(pid==0)
			{
		
				for( i=0;i<products;i++)
				{
					price=atoi((argv[i+1]));
					printf("Price %d at manufactor: %d\n", i+1, price);
					prices[i+1]=price;
            
					close(pipa[0]);  
					write(pipa[1], argv[i+1], 16); 
				}
				exit(EXIT_SUCCESS);
			}	 
			
			else /*distributer*/
			{
				wait(&pid);
				pid=fork();

				if(pid==0)
				{
					for(i=0;i<products;i++)
					{
						close(pipa[1]);
						read(pipa[0], temp_in,16);
						prices[i]=atoi(temp_in);               
						prices[i]+=(prices[i]*0.2);
               
						printf("Price %d at distributer: %d\n", i+1, prices[i]);
					}
					for(i=0; i<products;i++)	
					{
						sprintf(temp_out[i], "%d", prices[i]);
						close(pipa[0]);  
						write(pipa2[1], temp_out[i], 16); 
					}
					
					close(pipa[1]);
					exit(EXIT_SUCCESS);
				}
			else
            {
                wait(&pid);            
                pid=fork();
                if(pid==0) 
                {
                   for(i=0; i<products;i++)
                   {
                      
                      close(pipa2[1]);  
                      read(pipa2[0], temp_in, 16);
                      prices[i]=atoi(temp_in);
                                        
                      prices[i]+=(prices[i]*0.3);                  
                      printf("Price %d at dealer: %d\n", i+1, prices[i]);
                   }
                   for(i=0; i<products;i++)
                   {
                      
                      sprintf(temp_out[i], "%d", prices[i]);
                      close(pipa2[0]); 
                      write(pipa[1], temp_out[i], 16);
                      
                   }
                   exit(EXIT_SUCCESS);                   
                }
			else
            {
				wait(&pid);
				pid=fork();
                if(pid==0) 
                {
					for(i=0; i<products;i++)
					{                        
						close(pipa[1]); 
						read(pipa[0], temp_in, 16);
						prices[i]= atoi(temp_in);
						printf("Price %d at consumer: %d\n", i+1, prices[i]);
                    }                      
                    exit(EXIT_SUCCESS);                   
                }
			}


			} 
			}
		}
	
	return EXIT_SUCCESS;
	}
If anyone could shed some light upon my problem I would be grateful!
 
Old 12-06-2010, 05:55 AM   #2
SuchANewb
LQ Newbie
 
Registered: Nov 2010
Posts: 7

Original Poster
Rep: Reputation: 0
char temp_in[16]="";

how do I make the same with char temp_out[50][16]; ?
 
  


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