trying to write to a file?? it's not working

[Strawberry11]

i've been trying to write an application so that the data entered is saved but it writes over the previous entry made. i was wondering if anyone could help me. i've been trying to sort the problem all day now
i have to add sort and search to the application but cannot succeed in finishing this until i can write to a file.

your feedback will be greatly recieved.
Strawberry11

[Salem]

What sort of file - text or binary ?
How did you open the file - "w" "wb" "ab" ??
How did you write to the file - did you fwrite() and fseek() or something else?
Are you trying to read what you wrote without doing fflush() ?

Post yer code!

[itsme86]

I'm assuming you're using something like fopen("foobarbaz", "w");

The "w" mode will erase anything in the file. Instead, try using the "a" mode like fopen("foobarbaz", "a");. The "a" is for "append".

Next time, please post your code so that helping you isn't such a guessing game.

[Strawberry11]

sorry
am opening it with wb
and using fwrite

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

#define MAX 10

 struct Lib{
	char Title[50];
	char Author[30];
	char Publisher[30];
	char Year[10];
	char ISBN[10];
	char Edition[5];
  }Lib_info[MAX];

//  struct LibCard NewRec[80];
 
void enter(void);
void list(void);
void delete(void);
void init_list(void);
int menu_select(void);
void load (void);
void save(void);
void SearchTitle(void);


void main(void)
{
  

      	char choice;
      	init_list();
	load();

for (;;) {
      
	choice = menu_select();
	switch(choice){
		case 1:enter();
		break;
		case 2: delete();
		break;
		case 3:list();
		break;
                case 4:save();
		break;
		case 5:SearchTitle();
		break;
		case 6:exit(0);
}
}
}
//initialise the list
 
void init_list(void)
{
	register int t;
	for (t=0;t<MAX; ++t)Lib_info[t].Title[0] = '\0';
}
//get a menu selection

	menu_select(void)
	{char s [80];
	int c;

	printf("1.Enter\n");
	printf("2.Delete\n");
	printf("3.List\n");
	printf("4.Save\n");
	printf("5.Search\n");
	printf("6.exit\n");

	do{
		printf("Enter choice ");
 		gets(s);
		c = atoi(s);

	}while(c<0 ||c> 6);
	return c;
}

// ADD NEW ENTRIES TO THE FILE

void enter(void)
{
	int slot;
	char s[80];
	slot = find_free();
	if (slot==-1){
  		printf("LIst Full");
	return;
	}

	printf("Enter Title: ");
	gets(Lib_info[slot].Title);

	printf("Enter Author: ");
	gets(Lib_info[slot].Author);

	printf("Enter Publisher: ");
	gets(Lib_info[slot].Publisher);

	printf("Enter Year: ");
	gets(Lib_info[slot].Year);

	printf("Enter ISBN: ");
	gets(Lib_info[slot].ISBN);

	printf("Enter Edition: ");
	gets(Lib_info[slot].Edition);


}

void SearchTitle (void)
{
	int slot;
	slot = search();
	if (slot==-1){
  		printf("Not FOund");
	return;

	}
}



find_free(void)
{
	register int t;
	for(t=0; Lib_info[t].Title[0] && t<MAX; ++t){

		if (t==MAX) return -1;{
		return t;
		}
	}
}

search(void)
{
	register int t;
	char s[80];
	char s2 [80];
	int c;

	printf("Enter TITLE: ");
	gets(s);
	c = atoi(s);

for(t=0; Lib_info[t].Title[0] &&t<MAX; ++t){
if (t==MAX) return -1;{
//	if (Lib_info[t].Title  ){
//                s2 = Lib_info[t].Title[0];
//		printf("entry found");
//	}
return t;
}
}

}

//DELETE THE SELECTED ITEM

void delete(void)
{
	register int slot;
	char s[80];
	printf("enter record #: ");
	gets(s);
	slot = atoi(s);

	if (slot>=0 && slot < MAX)
		Lib_info[slot].Title[0] = '\0';
}


//DISPLAY THE LIST OF ENTRIES TO THE SCREEN

void list(void)
{
	register int t;
	for (t=0; t<MAX; ++t) {
		if (Lib_info[t].Title[0]) {
			printf("%s\n",Lib_info[t].Title);
			printf("%s\n",Lib_info[t].Author);
			printf("%s\n",Lib_info[t].Publisher);
			printf("%s\n",Lib_info[t].Year);
			printf("%s\n",Lib_info[t].ISBN);
			printf("%s\n",Lib_info[t].Edition);
		}
	}
	printf("\n\n");
}

//SAVE THE LIB STRUCTURE DETAILS TO THE LIBRARY FILE

void save(void)
{
	FILE *fp;
	register int i;
	if ((fp=fopen("LibCard.txt","wb"))==NULL){
		printf("cannot open file \n");
		return;

	}
for (i=0; i<MAX; i++)
  if (*Lib_info[i].Title)
	if (fwrite(&Lib_info[i],
		sizeof(struct Lib),1,fp)!=1)
			printf("File Write error\n");

fclose(fp);
}

//LOAD THE DETAILS OF THE LIBRARY FILE TO THE LIB STRUCTURE

void load (void)

{
	FILE *fp;
        
	register int i;
	if ((fp=fopen("LibCard.txt","rb"))==NULL){
		printf("cannot open file \n");
		return;
	}
init_list();
for (i=0; i<MAX; i++)
	if (fread(&Lib_info[i],
		sizeof(struct Lib),1,fp)!=1){
			if (feof(fp)) break;
			printf("File Write error\n");
}
fclose(fp);
}

[Salem]

Threads merged

[Salem]

> void main(void)
http://faq.cprogramming.com/cgi-bin/...&id=1043284376

> gets(s);
http://faq.cprogramming.com/cgi-bin/...&id=1043284351

In find_free()
> if (t==MAX) return -1;
> return t;
Your braces make no sense, you just exit on the first pass of the loop anyway, whether you found a free slot or not
search() is similarly broken.

> register int t;
It's largely a waste of time trying to guess how modern compilers allocate registers. Optimisation techniques have come a long way in the past 30 years.

> #include <io.h>
Non-standard header file - I couldn't see any reason why you would want this file included.