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Full Discussion: pipe program in C
Top Forums Programming pipe program in C Post 302473549 by beandj on Sunday 21st of November 2010 09:49:27 AM
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
 

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wml::std::all(3)						     EN Tools							  wml::std::all(3)

NAME
wml::std:all - All of Standard (STD) category SYNOPSIS
#use wml::std::all DESCRIPTION
This includes all existing include files of the Standard (STD) category, i.e. all includes with prefix wml::std. The following files currently exist: wml::std::box(3) ... Easily Create Rectangular Box wml::std::case(3) ... Convert Tags to Upper or Lower Case wml::std::grid(3) ... Layout Grid wml::std::href(3) ... Enhanced Hyperlink wml::std::info(3) ... Page Information wml::std::lang(3) ... Multi-Lingual Support wml::std::label(3)... Labels and References wml::std::logo(3) ... Logo Insertion wml::std::page(3) ... Standard HTML Page Header and Footer wml::std::tags(3) ... Standard Support Tags wml::std::toc(3) ... Table of Contents Generation AUTHOR
Ralf S. Engelschall rse@engelschall.com www.engelschall.com REQUIRES
Internal: P1 External: -- SEE ALSO
wml::std::box(3), wml::std::case(3), wml::std::grid(3), wml::std::href(3), wml::std::info(3), wml::std::label(3), wml::std::lang(3), wml::std::logo(3), wml::std::page(3), wml::std::tags(3), wml::std::toc(3). EN Tools 2014-04-16 wml::std::all(3)
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