htmlify

// output file with the following characters converted to be html safe
// "    "
// '    '
// &    &
// <    &lt;
// >    &gt;
#pragma warning(disable:4996)

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

#define FALSE 0
#define TRUE 1
int main(int argc, char* argv[])
{
    char ch;
    FILE* read;
    // optional append file, else just pipe the stream in cmd: reader.exe read.txt > output.txt
    int appending = FALSE;
    FILE* append;

    if (argc == 2)
    {
        read = fopen(argv[1], "r");
        append = NULL;
    }
    else if (argc > 2) {
        read = fopen(argv[1], "r");
        append = fopen(argv[2], "a");
        appending = TRUE;
    }
    else {
        perror("Expected read file.\n");
        exit(EXIT_FAILURE);
    }

    if (read == NULL)
    {
        perror("Error while opening the file.\n");
        exit(EXIT_FAILURE);
    }

    if (appending == TRUE)
    {
        if (append == NULL)
        {
            perror("Error while opening the file.\n");
            exit(EXIT_FAILURE);
        }
    }

    while((ch = fgetc(read)) != EOF)
    {
        switch(ch){
            case  '<':
                if(appending == TRUE)
                    fputs("&lt;", append);
                else
                    printf("&lt;");
            break;
            case  '>':
                if (appending == TRUE)
                    fputs("&gt;", append);
                else
                    printf("&gt;");
            break;
            case  '&':
                if (appending == TRUE)
                    fputs("&amp;", append);
                else
                    printf("&amp;");
            break;
            case  '"':
                if (appending == TRUE)
                    fputs("&quot;", append);
                else
                    printf("&quot;");
            break;
            case '\'':
                if (appending == TRUE)
                    fputs("&apos;", append);
                else
                    printf("&apos;");
            break;
            default:
                if (appending == TRUE)
                    fputc(ch, append);
                else
                    printf("%c", ch);
        }
    }

    fclose(read);
    if (appending == TRUE)
        fclose(append);
    return 0;
}