Homework & Coursework Questions

#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);
}

if ( error_return == *open(...)){
  perror( "file_name_or_symbol" );
  exit( 1 );
 }
 .
 .
 .

while ( 1 == fscanf( ... )){
  fprintf(...);
 }

switch ( ret = read(...)){
 case -1:  // error handling
  perror( "read(...)" );
  exit( 1 );
 case 0:  // EOF
  exit(0);
 default:  // Good read
  char_in_buf += ret ;
  .
  .
  .
  break;
 }