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#include <stdio.h>
#include <stdlib.h>
#include <ctype.h>
#include <string.h>
#include <io.h>
#include <fcntl.h>
int main()
{
// String Storage
char mystring[100];
// Format into words
int character_scanner = 0;
int begin_word = 0;
// Compact
int file_discription;
int file_length;
char *buffer;
char word_pos[10];
char *words;
FILE *outfile; // DHH declare a pointer to a file control block.
// Create and open a file
/*
* DHH this is the line that was causing the most problems. The "r+" requires that
* input file already exist. Since it doesn't, the fopen failed and returned a null
* pointer as the FILE pointer. This caused later file operations to fail.
* Use "w+" if you want to create or overwrite an existing file.
*/
outfile = fopen("Hello_World.txt", "w+");
// ********************************
// Print a character string in the file, and set the cursor to the beggining
// ( DHH long string, multiple adjacent strings are concatenated by the compiler
// into one long string. This works as long as there are no % characters in it
// because it occupies the position of the format string in the fprintf function call)
// A safer implementation would be:
//
// fprintf(outfile, "%s", "Hello World. This would happen to be the string "
// "being tested for whitespace!\n");
//
// -or-
//
// fprintf(outfile, "%s\n", "Hello World. This would happen to be the string "
// "being tested for whitespace!\n");
fprintf(outfile, "Hello World. This would happen to be the \nstring being tested for whitespace!\n");
fseek(outfile, 0, SEEK_SET);
// ***************************************************************************
// Aquire the first string in the file
#if 0
/*
DHH This is the better way to comment out code (using #if 0).
First off it allows you to put old code back in place if you need
to try something else. Secondly, it is not subject to problems with
nested comments.
*/
fgets(mystring, 100, outfile);
#else /* DHH optional. */
#endif
// **************************
// Put declarations at top of code
// initialize variables here to check the character for a white space.
// **************************************
// Check each character for white space, start at the pointer(character_scanner
// end at NULL
/*
* DHH This version of fgets makes it unnecessary to search for every use of mystring
* to make sure you don't declare it with multiple lengths. I practice, the
* only constants I allow in my code are 1 and 0. Anything else is declared
* as a #define or a variable. It prevents a lot of unnecessary debuging later.
*/
while (fgets(mystring, sizeof mystring, outfile))
{
/*
* OK, we got a line of input for parsing.
* initialize the character scanner to start of line.
*/
character_scanner = 0;
/*
* Now we loop processing the line.
*/
while (mystring[character_scanner] != NULL) // DHH
{
begin_word = character_scanner;
if (!isspace(mystring[character_scanner]))
{
while (!isspace(mystring[++character_scanner]));
mystring[character_scanner++] = '\0';
}
else
{
begin_word = ++character_scanner;
}
}
}
// ***************************************
// Compact the first word in the string to the first character in the array
// ********************************
// set the buffer to the address of the string
file_discription = _open("Hello_World.txt", _O_RDONLY);
file_length = _filelength(file_discription);
buffer = (char*) malloc (file_length);
// Register spaces in the buffer to array word_pos
words = strchr(buffer, '\0');
while(words != NULL)
{
strcpy(word_pos, words);
words = strchr(buffer + 1, '\0');
}
// print the data at the specified address to the screen
printf(word_pos);
fclose(outfile);
}
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