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POWhat is the mistake in WRITE and READ?
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copied!<p>This is a small C program concerning pipes and processes, The Father process will create 2 child processes, the first will read the numbers out of a chain, the second will read the letters. I started by asking for the WORD, I didnt add protection this is just a test, so lets say about 20 letters, then the father process will write the numbers in the first pipe, and the letters in the second pipe, then he will create a child using fork(), if he's the child , he will read the numbers from the first pipe, if he's the father, then he will create another child, to read the letters.</p> <pre><code># include <stdio.h> # include <unistd.h> # include <string.h> # include <fcntl.h> main() { printf("I am the father, I will create 2 sons, the first will read the numbers , the second will read the letters\n"); char * word; printf("please type the word: \n"); scanf("%s",word); printf("Now 2 pipes will be created\n"); int fd1[2]; int fd2[2]; pipe(fd1); pipe(fd2); printf("Now the father will write numbers in the first pipe, and letters in the second\n"); int i; char numbers[20]; int j=0; char caracters[20]; int k=0; for (i=0;i<20;i++) { if(word[i]>='0' && word[i]<='9') //if number { close(fd1[0]); //closing reading write(fd1[1],word[i],2); } else { close(fd2[0]); write(fd2[1],word[i],2); } } printf("The father has wrote in the 2 pipes, now its time for the sons\n"); int f=fork(); if(f==0) //first son { for(i=0;i<20;i++) { close(fd1[1]); //closing writing read(fd1[0],numbers[j],strlen(numbers[j])+1); j++; } printf("first son read everything, he got %d Numbers\n", j); } else { f=fork(); if(f==0) { for(i=0;i<20;i++) { close(fd2[1]); //closing writing read(fd2[0],caracters[k],strlen(caracters[k])+1); k++; } printf("second son read everything, he got %d caracters\n", j); } } </code></pre> <p>after compiling : </p> <pre><code>In function 'main': Line 25: warning: passing argument 2 of 'write' makes pointer from integer without a cast Line 31: warning: passing argument 2 of 'write' makes pointer from integer without a cast Line 41: warning: passing argument 1 of 'strlen' makes pointer from integer without a cast Line 41: warning: passing argument 2 of 'read' makes pointer from integer without a cast Line 54: warning: passing argument 1 of 'strlen' makes pointer from integer without a cast Line 54: warning: passing argument 2 of 'read' makes pointer from integer without a cast Line 60: error: expected declaration or statement at end of input </code></pre>

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