I have to write a code using fork() function where one file i.e producer will open a DATA.txt file and add a character taken from testfile.txt file and pass the turn to consumer.c file which open the DATA.txt file again and take the character from the file and print it on screen. I know how the logic works but i am stuck with an infinite loop and doesn't know how to get out of it. any help will be appreciated. DATA and TURN cannot have more than one character at a time Following are the file for the program.
output:
Segmentation fault: 11
...
//main.c file
#include"header.h" // including the header file
int main(){
FILE* fp = fopen("TURN.txt","w+");
if(fp== NULL){
exit(1); // exit with an error
}
fputc('0',fp) ; // writing to file TURN.txt
fclose(fp);
// including consumer.c and producer.c files
// now we have access to functions in consumer.c and producer.c
int pid = fork();
if(pid == -1) exit(1) ; // Failure exit
if(pid == 0){consumer();}
if(pid != 0){producer();}
return 0 ; // success(Erfolg)}
..
//producer.c file
#include"header.h"
void producer(){
char t; // for TURN LOOP
char p;
FILE *fp = fopen("testfile.txt", "rt");
while(!feof(fp)){
do{
FILE *TURN = fopen("TURN.txt", "rt");
t = fgetc(TURN) ;
fclose(TUdRN); // closing turn file
} while(t!= '0') ; // wait for turn
FILE *DATA = fopen("DATA.txt", "w+"); // opening data file to write a character in it
p = fgetc(fp); // getting character from testfile to write in data file
fputc(p, DATA);
fclose(DATA) ; // closing data file
FILE *TURN = fopen("TURN.txt", "r+"); // opening turn file to change the value to 1 and pass the turn to consumer.c
fputc('1', TURN); // overwriting 1 in the turn file so now turn as only 1 in it.
fp++ ; // incrementing the file pointer
} // end of the while loop
fclose(fp);
} ...
#include"header.h" // including the header file
void consumer (){
char c;
char t;
while(1){
do{
FILE *ft = fopen("TURN.txt","r"); // opening turn file
t = fgetc(ft) ;
fclose(ft) ; // closing the turn file
} while( t!= '1' );
FILE *dt = fopen("DATA.txt","r"); // opening data file to read from it
c = fgetc(dt);
if(c =='\0'){
break ;
}
//else data file in not empty print the character on the screen in same order as testfile
printf("%c",c) ;
FILE *ft = fopen("TURN.txt","r+");
fputc('0',ft); // producer.c turn
//closing both turn and data file
fclose(dt);
fclose(ft) ;
} // end of while loop
} // end of consumer method
...
// header files for consumer. and producer.c and main.c
#ifndef HEADER_H // Including guards to avoid reimplimentation
#define HEADER_H
#include<stdio.h>
#include<stdlib.h>
#include<unistd.h>
#include<string.h>
// function signatures from the producer.c and consumer.c
void producer();
void consumer();
#endif // !LIST_H
...
//make file
program: main.o consumer.o producer.o header.h
gcc -o program main.c consumer.c producer.c
main.o: consumer.c producer.c header.h
gcc -c consumer.c producer.c
consumer.o: consumer.c header.h
gcc -c consumer.c
producer.o: producer.c header.h
gcc -c producer.c
clean:
rm *.o program.o
