C program to replace specific line in a file

Write a C program to replace specific line in a file.

  #include <stdio.h>
  #include <string.h>
  #define MAX 256

  int main() {
        FILE *fp1, *fp2;
        int lnum, lineCount = 0;
        char file[MAX], string[MAX];
        char newline[MAX], temp[] = "temp.txt";

        /* get the input file name from the user */
        printf("Enter your input file name:");
        fgets(file, MAX, stdin);
        file[strlen(file) - 1] = '\0';

        /* open the input file in read mode */
        fp1 = fopen(file, "r");

        /* error handling */
        if (!fp1) {
                printf("Unable to open the input file!!\n");
                return 0;
        }

        /* open the temporary file in write mode */
        fp2 = fopen(temp, "w");

        /* error handling */
        if (!fp2) {
                printf("Unable to open a temporary file to write!!\n");
                fclose(fp1);
                return 0;
        }

        /* get the new line from the user */

        printf("Enter your new input line(to replace):");

        fgets(newline, MAX, stdin);

        /* get the line number to delete the specific line */

        printf("Enter the line no of the line you want to replace:");

        scanf("%d", &lnum);

        /*

         * copy all contents to the temporary file other

         * other than line belongs to input line number.

         */

        while (!feof(fp1)) {

                strcpy(string, "\0");

                fgets(string, MAX, fp1);

                if (!feof(fp1)) {

                        lineCount++;

                        /* skip the line at given line number */

                        if (lineCount != lnum) {

                                fprintf(fp2, "%s", string);

                        } else {

                                /* replacing with new input line */

                                fprintf(fp2, "%s", newline);

                        }

                }

        }

        /* close the opened files */

        fclose(fp1);

        fclose(fp2);

        /* remove the input file */

        remove(file);

        /* rename the temporary file */

        rename(temp, file);

        return 0;

  }

  Output:

  jp@jp-VirtualBox:~/$ cat second.txt 
  0123456789
  abcdefghij
  0123456789
  abcdefghij
  0123456789

  jp@jp-VirtualBox:~/$ ./a.out
  Enter your input file name:second.txt
  Enter your new input line(to replace):abcedfghij
  Enter the line no of the line you want to replace:5

  jp@jp-VirtualBox:~/$ cat second.txt 
  0123456789
  abcdefghij
  0123456789
  abcdefghij
  abcedfghij

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