#include <stdio.h>

int main()
{
	char str [256];
	puts("Enter some text you would like to add to the file:");
	fgets(str,255,stdin);
	FILE * pFile;
	pFile = fopen("myfile.txt", "a");
	if (pFile==NULL)
	{
		pFile = fopen("myfile.txt", "w");
	}
	else if (pFile!=NULL)
	{
		fputs(str,pFile);
		fclose(pFile);
	}
	return 0;
}