Problem with Loops and File Handling in C

Question

Can't figure out the solution to solve the infinite iteration
Thinking of having done wrong the application of fgetc() function but still don't know how to solve.

This program basically finds a word in a given file and then changes it with what the user/programmer wants.

Here are the main and the solving function:

int main(int argc, char **argv)
{
   FILE *fPtr = NULL;

   newFile(&fPtr, "ReadFile.txt");
   writeFile("ReadFile.txt", "This is not a Random Access File
Now just see what happens!");
   readFile("ReadFile.txt");

   replaceWord("ReadFile.txt", "happens!", "happened here!
 Did you see it?");
   readFile("ReadFile.txt");

   return 0;
}
//^ Problem -> Infinite Loop
int findWordPosition(const char *fileName, const char word[]) {
   FILE * fPtr = NULL;

   fPtr = fopen(fileName, "r");
   check(fPtr);
   int lenght = strlen(word);

   int position;
   int i, j = 0;
   char ch;

   //^ (- Problem Here -) Can't figure i get an infinite loop 
   for (i = 0; (ch = fgetc(fPtr)) != EOF || j < lenght; ++i) {
      puts("Hello");
      if (ch == word[j]) {
         if (j == 0) { 
            position = i;
         }
         else if (j == (lenght - 1)) {
            puts("
Word Found");
            return position;
         }
         ++j;
      }
      else {
         j = 0;
      }
   }
   puts("
Word not found!");
   return 0;
}

Here is the entire code

#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <conio.h>

void check(FILE *fPtr);
int findWordPosition(const char *fileName, const char word[]);

void newFile(FILE **fPtr, const char *fileName);
void writeFile(const char *fileName, const char *string);
void readFile(const char *fileName);
void replaceWord(const char *fileName, const char *word, const char *newWord);

int main(int argc, char **argv)
{
   FILE *fPtr = NULL;

   newFile(&fPtr, "ReadFile.txt");
   writeFile("ReadFile.txt", "This is not a Random Access File
Now just see what happens!");
   readFile("ReadFile.txt");
   
   replaceWord("ReadFile.txt", "happens!", "happened here!
 Did you see it?");
   readFile("ReadFile.txt");

   return 0;
}

void check(FILE *fPtr) {
   if (!fPtr) { puts("File Insesistente"); exit(1); }
}

void newFile(FILE **fPtr, const char *fileName) {
   *fPtr = fopen(fileName, "w");
   check(*fPtr);

   fclose(*fPtr);
}

void writeFile(const char *fileName, const char *string) {  
   char *s;
   FILE *fPtr = NULL;

   fPtr = fopen(fileName, "a");
   check(fPtr);
   
   fprintf(fPtr, "%s", string);

   fclose(fPtr);
}

void readFile(const char *fileName) {
   FILE * fPtr = NULL;
   char ch;
   
   fPtr = fopen(fileName, "r");
   check(fPtr);

   while ((ch = fgetc(fPtr)) != EOF) {
      printf("%c", ch);
   }

   fclose(fPtr);
}

//^ Problem -> Infinite Loop
int findWordPosition(const char *fileName, const char word[]) {
   FILE * fPtr = NULL;
   
   fPtr = fopen(fileName, "r");
   check(fPtr);
   int lenght = strlen(word);
   
   int position;
   int i, j = 0;
   char ch;

   //^ (- Problem Here -) Can't figure i get an infinite loop 
   for (i = 0; (ch = fgetc(fPtr)) != EOF || j < lenght; ++i) {
      puts("Hello");
      if (ch == word[j]) {
         if (j == 0) { 
            position = i;
         }
         else if (j == (lenght - 1)) {
            puts("Word found");
            return position;
         }
         ++j;
      }
      else {
         j = 0;
      }
   }
   puts("
Word not found");
   return 0;
}

void replaceWord(const char *fileName, const char *word, const char *newWord) {
   FILE *fPtr = NULL;
   int position;
   
   fPtr = fopen(fileName, "w+");
   check(fPtr);
   
   position = findWordPosition(fileName, word);

   fseek(fPtr, position, SEEK_SET);
   fputs(newWord, fPtr);
   fprintf(fPtr, "%s", newWord);
}

question from:https://stackoverflow.com/questions/65835913/problem-with-loops-and-file-handling-in-c

Answer 1

Waitting for answers