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

#define MAX_FILE_NAME_LEN 1023

int main( )
{
    int maxLen = 2;
    int i = 0;
    char *str = (char *) malloc( maxLen );
    int ch;
    FILE *fp;
    char fileName[ MAX_FILE_NAME_LEN + 1 ];
    char formatString[ 25 ];


    printf( "Please enter a file name: " );

    /* Instead of using %s for scanf, we want %1023s to avoid overflow */
    /* It's not the easy to do; have to create a string for it */
    /* And watch out for % signs */
    sprintf( formatString, "%%%ds", MAX_FILE_NAME_LEN );
    if( scanf( formatString, fileName ) != 1 )
    {
        fprintf( stderr, "Cannot get a filename\n" );
        return 1;
    }


    printf( "Opening %s\n", fileName );
    fp = fopen( fileName, "r" );
    if( fp == NULL )
    {
        fprintf( stderr, "Error opening %s\n", fileName );
        return 1;
    }

    /* Build it character at a time */
    while( ( ch = fgetc( fp ) ) != EOF )
    {
        if( i + 1 >= maxLen )  // so there is room for '\0' at end if needed
        {
            maxLen *= 2;
            str = (char *) realloc( str, maxLen );
        }
        str[ i++ ] = ch;
    }
    str[ i ] = '\0';

   
    if( strlen( str ) < 4000 )
        printf( "%s\n", str );
    
    printf( "Read %d (%d) characters\n", strlen( str ), i );

    return 0;
}