Member Avatar for chelo77

I'm having problems here with this function i'm making, i need to make function that will write to a text file. This function has to ask the user for the file name and check if it exists. If this is all good then it will write the string in the buffer to the text file. The string is no bigger than 60chars.
so far i have started it but i am having diffuculty in understanding it, my text book isn't the best help either. Below is my function so far

void write_string(File *fp, char *s)
{
File *ptr;
int i;

ptr == fopen(fp, "w");
if (ptr == NULL)

}

My problem is what is fp, its coming from the main but what is it exactly?
Here is my code for the whole program please view if it makes more sense..Please i need some help

#include <stdio.h>
#include <stdlib.h>
#include <ctype.h>
#include <conio.h>
#include <string.h>
#include <iostream.h>


//void instruct(void);
//void classify(char cInput[], float fstats[], int i, int iOdd, int iEven, int iUpper,
		  // 	 int iLower, int iOaverage, int iEaverage);
void instruct(char *cInput);
void summary(float fstats[], int i, int iOdd, int iEven, int iUpper,
			 int iLower, int iOaverage, int iEaverage);
//int  count(char cChoice, char cInput[]);
int  search(char cGet, char cInput[]);
void menu(void);
int modify ( const char x, const char y, char *s);
void classify(char *cInput, float *fstats);
int count(char cChoice, char *cInput);
void write_string(File *fp, char *s)

void main(void)
{
										
	int iOdd=1, iEven=2;
	int i=0, iCheck=0, j, iChange = 0;
	int iUpper=3, iLower=4;
	int iOaverage =5, iEaverage=6;
	char cInput [61] = {"0"};
	float fstats[7]={0,0,0,0,0,0,0};
	char cPick , cChoice, cGet, cReplace;

	cInput[i]='\0';
	menu();
	cPick = getche();

	for (;cPick != '9'; )
	{
		switch(cPick)
		{
			case '1':  system("cls");
					   cInput[i]='\0';
					   for (j=0; j<=6; j++)
						   fstats[j]=0;
			           instruct(cInput);
			           //classify(cInput,fstats,i,iOdd,iEven,iUpper,iLower,iOaverage,iEaverage);
					   classify(cInput,fstats);
			           break;

	        case '2':  iCheck = strlen(cInput);
			           if (iCheck >=1)
					   {
							system("cls");
				            for (j=0; j<iCheck;j++)
								printf("%c", cInput[j]);
							printf("\n");
					   }
					   else
						   printf("\nThere is no string in the memory please input a string first\n");
					   //cin.clear(); 
					   //cin.ignore(80,'\n'); 
			           //cin.get();
					   system("pause");
			           break;

	        case '5':  iCheck = strlen(cInput);
				       if (iCheck >=1)
					   {
						   system("cls");
					       printf("Please input the character to search:");
					       cGet = getche();
						   if (search(cGet, cInput) > 0)
							   printf("\nthe character occurs first at the index %d\n",search(cGet,cInput));
						   else
							   printf("\nthere are no occurences of that character\n");
					   }
					   else
						   printf("\nThere is no string in the memory please input a string first\n");
					       
					   //cin.get();
					   system("pause");
					   break;

	        case '6':  iCheck = strlen(cInput);
				       if (iCheck >=1)
					   {
						   system("cls");
					       printf("please input character:");
					       cChoice = getche();
						   if (count(cChoice,cInput) >0)
							   printf("\nThere are %d occurences of the character %c\n", count(cChoice, cInput), cChoice);
						   else 
							   printf("\nthere are no occurences of that character\n");
					   }
				       else
						   printf("\nThere is no string in the memory please input a string first\n");
					   //cin.get();
					   system("pause");
				       break;

	        case '8':  iCheck = strlen(cInput);
			           if (iCheck >=1)
					   {
				           system("cls");
				           summary(fstats,i,iOdd,iEven,iUpper,iLower,iOaverage,iEaverage);
					   }
			           else
						   printf("\nThere is no string in the memory please input a string first\n");
					   //cin.get();
					   system("pause");
			           break;

			case '7':  iCheck = strlen(cInput);
			           if (iCheck >=1)
					   {
						   system("cls");
					       printf("character to be replaced:");
					       cChoice = getche();
						   if (count(cChoice,cInput) >0)
						   {
							   printf("\nWith:");
							   cReplace = getche();
							   iChange = modify(cChoice,cReplace,cInput);
							   printf("\nThere have been %d changes made to the string\n", iChange);
							   classify(cInput, fstats);
						   }
						   else
							   printf("\nthere are no occurences of that character\n");
					   }
					   else
						   printf("\nThere is no string in the memory please input a string first\n");
					   system("pause");
			           break;
		}
	system("cls");
	menu();
	cPick = getche();
	}
printf("\n\n");

}

void instruct(char *cInput)
{
	printf("To terminate the program, strike the spacebar or Enter.\n\n\n");
	printf("Next key>");

	int j =0;
	char cTemp;

	cTemp = getche();

	for(;((cTemp != 32) && (cTemp!= 13)); )	//ascii 32 for blank and 13 for carriage return
	{
		if (j <=59)
		{
			if ((cTemp != 8) && (cTemp != 9))
			{
				*cInput = cTemp;
				*(cInput + 1)  = '\0';
				//fstats[i]++;
				j++; 
				cInput = cInput + 1;
			}
			cTemp = getche();
		}
		else 
		{
			printf("\nYou cannot enter more than 60 characters, the first 60 characters will remain\n");
			//printf("hit enter to continue");
			//cin.get();
			system("pause");
			break;
		}
	}



}

void classify(char *cInput ,float *fstats)
{
	int j;
	int iResult =0;
//	int i; 
	float * pstatbeg;
	char * pInputbeg;

	pInputbeg = cInput;
	pstatbeg = fstats;//char cTemp;

	//cTemp = getche();
	for (j=0; j<=6; j++)
		fstats[j]=0;
	//for(;((cTemp != 32) && (cTemp!= 13)); )	//ascii 32 for blank and 13 for carriage return
	for ( ; *cInput !='\0'; cInput = cInput + 1)
	{
		//if ( j<=59)
	//	{
			if (isalpha(*cInput) != 0)
			{
				if (isupper(*cInput) !=0)
					fstats [3]++;
				else
					fstats[4]++;
			}

			if(isdigit(*cInput) !=0)
			{
				if( (*cInput%2) == 0)
				{
					fstats[2]++;
					iResult = *cInput - '0';
					*(fstats +6) = (*(fstats + 6) + iResult);
				}

				else 
				{
					fstats[1]++;
					iResult = *cInput - '0';
					*(fstats + 5) = (*(fstats + 5) + iResult);
				}
			}

			fstats[0]++;
			fstats = pstatbeg;
	}

		 //   if ((cTemp != 8) && (cTemp != 9))
		//	{
		//		cInput[j]= cTemp;
		//		cInput[j+1] = '\0';
		//		fstats[i]++;
		//		j++; 
		//	}
			//	cTemp = getche();
	//	}
	//	else 
	//	{
	//		printf("\nYou cannot enter more than 60 characters, the first 60 characters will remain\n");
			//printf("hit enter to continue");
			//cin.get();
	//		system("pause");
	//		break;
	//	}
	//}// for loop

	if (*(fstats +2) ==0)
		*(fstats +6) = 0;
	else 
		*(fstats + 6) = *(fstats+6)/(*(fstats +2));

	if (*(fstats + 1) ==0)
		*(fstats + 5) =0;
	else
		*(fstats + 5) = *(fstats + 5) /(*(fstats +1));
}

void summary(float fstats[], int i, int iOdd, int iEven, int iUpper,
			 int iLower, int iOaverage, int iEaverage)
{
	system("cls");

	printf("Thank you! Your summary:\n\n");
	printf("Total number of keystrokes entered:%.f\n", fstats[i]);
	printf("Upper case alphabetic characters:%.f\n", fstats[iUpper]);
	printf("Lower case alphabetic characters:%.f\n", fstats[iLower]);
	printf("Even digits:%.f\n", fstats[iEven]);
	printf("Odd digits:%.f\n", fstats[iOdd]);
	printf("Average value of the even digits entered:%.2f\n", fstats[iEaverage]);
	printf("Average value of the odd digits entered:%.2f\n", fstats[iOaverage]);

}

int count(char cChoice, char *cInput)
{
	int i, iNum, iTotal =0;

	iNum = strlen(cInput);
	for ( i=0; i<iNum; i++, cInput = cInput + 1)
	{
		if (cChoice == *cInput)
			iTotal++;
	}

	return iTotal;
}


int search(char cGet, char *cInput)
{
	int i, iIndex=0, iNum=0;

	iNum = strlen(cInput);
	for (i=0; i < iNum; i++)
	{
		if (cGet == cInput[i])
		{
			iIndex = i;
			iIndex++;
		    break;
		}
	}

	return iIndex;
}

void menu(void)
{
	printf("1.  Enter a string of characters\n");
	printf("2.  Display the current string\n");
	printf("3.  Write current string to file\n");
	printf("4.  Read a string from a file\n");
	printf("5.  Search for a character\n");
	printf("6.  Count occurences of a specific character\n");
	printf("7.  Replace all occurences\n");
	printf("8.  Produce a summary report on the current string\n");
	printf("9.  Exit\n\n");

}

int modify ( const char x, const char y, char *s)
{
	int iNum, j, i=0;

	iNum = strlen(s);
	for ( j=0; j < iNum; j++, s= s+1)
	{
		if (x == *s)
		{
			*s = y;
			i++;
		}
	}

	return i;
}

void write_string(File *fp, char *s)
{
	File *ptr;
	int i;

	ptr == fopen(fp, "w");
	if (ptr == NULL)
		


}
  • 3 Contributors
  • 3 Replies
  • 223 Views
  • 1 Year Discussion Span
  • Latest Post Latest Post by Aia

Dani AI

Generated

Short version: the bug is a type/usage mismatch. You either pass a filename (a char *) to a function that calls fopen, or you pass an already-open FILE * and just write to it. already pointed out two concrete mistakes (using File instead of standard FILE, and == instead of =), and is right that fopen expects the file name as the first argument and the mode string as the second.

Choose one of these two safe patterns.

Open-inside-function (function accepts a filename, opens, writes, closes):

int write_to_filename(const char *filename, const char *buf)
{
    FILE *fp = fopen(filename, "w");
    if (!fp) return -1;            /* fopen failed */
    if (fputs(buf, fp) == EOF) { fclose(fp); return -2; }
    fclose(fp);
    return 0;                      /* success */
}

Caller-opens-file (function accepts a ready FILE * and just writes):

int write_to_stream(FILE *out, const char *buf)
{
    if (!out) return -1;
    if (fprintf(out, "%s", buf) < 0) return -2;
    return 0;
}

Quick practical checklist and troubleshooting notes:

  • Include <stdio.h> and <string.h>. Use int main(void) not void main.
  • If you want to check "does the file exist?" first, try fopen(name, "r") (or use _access on Windows). Opening with "w" will create/truncate the file.
  • Remove the trailing newline when reading a filename (use fgets + strip '\n').
  • Always test fopen and the write calls (fputs/fprintf) for errors, and always fclose.
  • Ensure the buffer you write is NUL-terminated and within the 60-char limit.

Apply one of the two patterns above, and the symptoms you saw (type mismatch, failed fopen call, accidental equality operator) will be resolved.

Recommended Answers

All 3 Replies

Member Avatar for mcldev

When you fopen() a file the first argument is the File Name and the second argument is the file mode. For example, lets say we had a file name called "Foo.Bar". We would do the following:

File *fp = fopen("Foo.Bar", "w);
fp->write(....
fp->close();
Member Avatar for Aia

There's quite a few things wrong in you function.
Compare with this.
File is not the same that FILE.
File *fp is not a string.
ptr == fopen is not the same that ptr = fopen.

void write_string( char *fp, char *s)
{
    FILE *ptr;
    int i;

    ptr = fopen( fp, "w");
    if (ptr == NULL);

}
Member Avatar for Aia

>My problem is what is fp, its coming from the main but what is it exactly?

I'll tell you what exactly is. It is a function from The Outer Limits. It's so far out there that it doesn't even get call once inside main. And fp is nothing more that another alternative dimension or reality if you will.

Maybe this link can help anyone that searchs for this post.
Click here.

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