WC in C with different child processes [duplicate] - c

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Here is the final result i got so far for a simulator of wc linux command. I have to accomplish an output like this
This is child process 0, the number of lines is x
This is child process 1, the number of words is y
This is child process 2, the number of lines is z
The code i wrote is this one:
#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <errno.h>
#include <string.h>
#include <stdlib.h>
char* concat(char *s1, char *s2)
{
char *result = malloc(strlen(s1)+strlen(s2)+1);
strcpy(result, s1);
strcat(result, s2);
return result;
}
int countLines(FILE *f){
int count = 0;
char ch;
while ((ch = fgetc(f)) != EOF){
if (ch == '\n')
count++;
}
return count;
}
int countWords(FILE *f){
int countW = 0;
char ch;
while ((ch = fgetc(f)) != EOF){
if (ch == ' ')
countW++;
}
return countW;
}
int countChars(FILE *f){
int chars = 0;
char ch;
while ((ch = fgetc(f)) != EOF){
chars++;
}
return chars;
}
int main(int argc, char** argv)
{
int lineCount = 0;
int wordCount = 0;
int charCount = 0;
int n = 3;
int i,status;
int pids[3];
char *theprogram = argv[0];
char *thefile = argv[1];
if ( argc !=2 )
{
printf( "Help: %s filename\n", argv[0]);
}
else{
FILE *file = fopen( argv[1], "r");
if(file == 0){
char *sub = concat(theprogram, ": ");
char *middle = concat(sub, thefile);
perror(middle);
}
else{
for (i = 0; i < n; i++) {
pids[i] = fork();
if ( pids[i] < 0) {
perror("fork");
exit(-1);
} else if (pids[i] == 0) {
if (i==0){
lineCount += countLines(file);
printf("This is child proccess %d, and the number of lines is %d\n", i+1, lineCount);
exit(0);
}
else if (i==1){
wordCount += countWords(file);
printf("This is child proccess %d, and the number of words is %d\n", i+1, wordCount);
exit(0);
}
else {
charCount += countChars(file);
printf("This is child proccess %d, and the number of characters is %d\n", i+1, charCount);
exit(0);
}
}
}
return 0;
}
}
}
This is the actual output i am getting:
% ./a.out mywc.c
This is child proccess 2, and the number of words is 0
This is child proccess 1, and the number of lines is 64
This is child proccess 3, and the number of characters is 0
This is child proccess 3, and the number of characters is 0
This is child proccess 2, and the number of words is 0
This is child proccess 3, and the number of characters is 0
This is child proccess 3, and the number of characters is 0
What am I doing Wrong here? I am very new to C programming so not sure what i am missing.
Thanks.
EDIT
Exited the exit codes but can not get the word count and the character count right now.

Answer 1

The right code for my problem is here:
#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <errno.h>
#include <string.h>
#include <stdlib.h>
char* concat(char *s1, char *s2)
{
char *result = malloc(strlen(s1)+strlen(s2)+1);
strcpy(result, s1);
strcat(result, s2);
return result;
}
int countLines(char *f){
FILE *file = fopen(f, "r");
int count = 0;
char ch;
while ((ch = fgetc(file)) != EOF){
if (ch == '\n')
count++;
}
return count;
}
int countWords(char *f){
char buffer[1];
FILE *file = fopen(f, "r");
int countW = 0;
enum states { WSP, WRD };
int state = WSP;
char last = ' ';
while (read(fileno(file),buffer,1) == 1 )
{
if ( buffer[0]== ' ' || buffer[0] == '\t' || buffer[0]=='\n' )
{
state = WSP;
}
else
{
if ( state == WSP )
{
countW++;
}
state = WRD;
}
last = buffer[0];
}
return countW;
}
int countChars(char *f){
FILE *file = fopen(f, "r");
int chars = 0;
char ch;
while ((ch = fgetc(file))){
if (ch == EOF) break;
chars++;
}
return chars;
}
int main(int argc, char** argv)
{
int lineCount = 0;
int wordCount = 0;
int charCount = 0;
int n = 3;
int i,status;
int pids[3];
char *theprogram = argv[0];
char *thefile = argv[1];
if ( argc !=2 )
{
printf( "Help: %s filename\n", argv[0]);
}
else{
FILE *file = fopen( argv[1], "r");
if(file == 0){
char *sub = concat(theprogram, ": ");
char *middle = concat(sub, thefile);
perror(middle);
}
else{
for (i = 0; i < n; i++) {
pids[i] = fork();
if ( pids[i] < 0) {
perror("fork");
exit(-1);
} else if (pids[i] == 0) {
if (i==0){
lineCount = countLines(argv[1]);
printf("This is child proccess %d, and the number of lines is %d\n", i+1, lineCount);
exit(0);
}
else if (i==1){
wordCount = countWords(argv[1]);
printf("This is child proccess %d, and the number of words is %d\n", i+1, wordCount);
exit(0);
}
else {
charCount += countChars(argv[1]);
printf("This is child proccess %d, and the number of characters is %d\n", i+1, charCount);
exit(0);
}
}
}
return 0;
}
}
}