C Programming Code Examples

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C Program to Join Lines of Two given Files and Store them in a New file

C Program to Join Lines of Two given Files and Store them in a New file

    #include <stdio.h>

    #include <stdlib.h>

    /* Function Prototype */

    int joinfiles(FILE *, FILE *, FILE *);

    char ch;

    int flag;

    void main(int argc, char *argv[])

    {

        FILE *file1, *file2, *target;

        file1 = fopen(argv[1], "r");

        if (file1 == NULL)

        {

            perror("Error Occured!");

        }

        file2 = fopen(argv[2], "r");

        if (file2 == NULL)

        {

            perror("Error Occured!");

        }

        target = fopen(argv[3], "a");

        if (target == NULL)

        {

            perror("Error Occured!");

        }

        joinfiles(file1, file2, target);        /* Calling Function */

        if (flag == 1)

        {

            printf("The files have been successfully concatenated\n");

        }

    }

    /* Code join the two given files line by line into a new file */

    int joinfiles(FILE *file1, FILE *file2, FILE *target)

    {

        while ((fgetc(file1) != EOF) || (fgetc(file2) != EOF))

        {

            fseek(file1, -1, 1);

            while ((ch = fgetc(file1)) != '\n')

            {

                if (ch == EOF)

                {

                    break;

                }

                else

                {

                    fputc(ch, target);

                }

            }

            while ((ch = fgetc(file2)) != '\n')

            {

                if (ch == EOF)

                {

                    break;

                }

                else

                {

                    fputc(ch, target);

                }

            }

            fputc('\n', target);

        }

        fclose(file1);

        fclose(file2);

        fclose(target);

        return flag = 1;

    }