pipe program in C


 
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# 1  
Old 11-21-2010
pipe program in C

Hello guys,

my professor give me 2 days to study and make a program usign pipe, fork in c

i need to do a program

read a arq.txt
the father process read the file and the child print !

like this
Code:
#include <stdio.h>
#include <stdlib.h>
#include <sys/wait.h>

int main (){
        int std[2];
        FILE *fp;
        unsigned char c;
        pipe(std); 
        if(fork() == 0){ 
                close(0); 
                dup(std[0]); 
                close(std[0]);
                close(std[1]); 
                exit(0); 
        }else{
                close(1); 
                dup(std[1]); 
                close(std[0]); 
                close(std[1]); 
                if(fp = fopen("arq.txt", "rb")){ 
                        fscanf(fp, "%c", &c); 
                        while(!feof(fp)){ 
                                fprintf(stdout,"%c",c); 
                                fscanf(fp, "%c", &c);   
                        }
                        fclose(fp); 
                }
                wait(0); 
        }               
        return(0);
}

but the program doesn't work
and i dont know why

Last edited by jim mcnamara; 11-21-2010 at 11:12 AM.. Reason: code tags
# 2  
Old 11-21-2010
Please repost this in the homework forum. Thank you.
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