Finish my DATABASE using C

[joydeep1]

My C program for making a database which stores data and from which data can be retrieved is stated later.But I am not able to write the function for editing the stored items correctly.Please suggest a method.Also suggest :
1.mode in which file is to be opened in case 2 of the switch
2.Due to usage of scanf functions in case 1,strings with whitespaces cannot be entered correctly.Also if scanf("[^\n]",..)or gets(...) are used then problem is: stray '\n' is taken as input for the strings instead of taking any string from the user---please suggest!

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

typedef struct {
		char name[30];
		char company[50];
		char address[200];
		char pin[7];
		char web[30];
		}entry;
char name[30];char company[50];											
FILE *fpt;int menu(void);
entry *ptr,commodity;
int n=sizeof(entry);char ch,y;
void edit(entry *);
void main()
{
	int choice;
	do
	{
	choice=menu();
	switch(choice)
	{
		case 1:ptr=(entry *)malloc(sizeof(entry));
			fpt=fopen("data5.bin","a");
			printf("\nEnter the name of the commodity:");
			scanf("%s",ptr->name);
			printf("\nEnter the name of the producing company:");
			scanf("%s",ptr->company);
			printf("\nEnter the address of the producing company:");
			scanf("%s",ptr->address);
			printf("\nEnter the pincode:");
			scanf("%s",ptr->pin);
			printf("\nEnter the website of the producing company:");
			scanf("%s",ptr->web);
			fwrite(ptr,n,1,fpt);printf("ENTERED\n");
			fclose(fpt);
			continue;
		case 2:ptr=(entry *)malloc(sizeof(entry)); 
				fpt=fopen("data5.bin","r+");
		   do 
		   {
  			if (fread(&ptr->name, sizeof(ptr->name), 1, fpt) == 1 &&
      	fread(&ptr->company, sizeof(ptr->company), 1, fpt) == 1 &&
      	fread(&ptr->address, sizeof(ptr->address), 1, fpt) == 1 &&
      	fread(&ptr->pin, sizeof(ptr->pin), 1, fpt) == 1 && 
      	fread(&ptr->web, sizeof(ptr->web), 1, fpt) == 1)
      			{
    					printf("\n\nThe name of the commodity:");
						printf("%s",ptr->name);
						printf("\nThe name of the producing company:");
						printf("%s",ptr->company);
						printf("\nThe address of the producing company:");
						printf("%s",ptr->address);
						printf("\nPincode:");
						printf("%s",ptr->pin);
						printf("\nWebsite of the producing company:");
						printf("%s",ptr->web);
						printf("\nWant to EDIT this entry?(Enter y/n):");
						ch=getchar();
						if(ch==y) 
							edit(ptr);
			     }
   else if (feof(fpt)) 
          {
    printf("\n\nfinished reading file!\n");
    break;
    }
   else {
    printf("an error occured while reading the file!\n");
    break;
  	 }
} while (1);
		       fclose(fpt);continue;
	   case 3:printf("\nThank You for using!");exit(1);      								
	}
	}while(choice==1||choice==2);
	getch();
}
int menu(void)
{
	int choice;
	do{
		printf("Enter your choice:\n");
		printf("1.ADD a entry\n");
		printf("2.DISPLAY cum EDIT\n");
		printf("3.EXIT\n");
		scanf("%d",&choice);
	}while(choice!=1 && choice!=2 && choice!=3);
	return(choice);
}
void edit(entry *ptr)
{
	printf("\nWant to EDIT name of commodity?(y/n):");
	ch=getchar();
	if(ch==y)
	{		
			printf("\nEnter new commodity name:");
			scanf("%s",name);
			ptr->name=name;
	}
	printf("\nWant to EDIT name of company?(y/n):");
	ch=getchar();
	if(ch==y)
	{		
			printf("\nEnter new company name:");
			scanf("%s",company);
			ptr->company=company;
	}                      //....etc..etc.
	fwrite(ptr,n,1,fpt);
	return;
}

[Salem]

> FILE *fpt;int menu(void);
Don't mix declarations like this on one line

> void edit(entry *);
It's useful to also specify a variable name here, just to help document what is going on.
Eg, which do you prefer
strcpy ( char*, char *); // OK, but which way ?
strcpy ( char *dst, char *src ); // much more obvious what gets copied

> #include <conio.h>
Is a non-standard header you can well do without.

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

> ptr=(entry *)malloc(sizeof(entry));
Ptr is a poor name for a variable, and a global one is even worse.
Also, there is no need to cast malloc in C
http://faq.cprogramming.com/cgi-bin/...&id=1043284351

> fpt=fopen("data5.bin","a");
You should use the "b" mode as well, if you're using binary files (as is typical with fread and fwrite)

> if(ch==y)
Don't you mean
if(ch== 'y' )

> 2.Due to usage of scanf functions in case 1,strings with whitespaces cannot be entered correctly.Also if scanf("[^\n]",..)or gets(...) are used then problem is:
You should use fgets() for ALL input, which reads into a buffer

char buff[BUFSIZ];
fgets( buff, BUFSIZ, stdin );

Then you can validate, convert, copy the data to it's correct place.

Fixing the indentation would also help.

[joydeep1]

>
Due to usage of scanf functions in case 1,strings with whitespaces cannot be entered correctly.Also if scanf("[^\n]",..)or gets(...) are used then problem is:
You should use fgets() for ALL input, which reads into a buffer

char buff[BUFSIZ];
fgets( buff, BUFSIZ, stdin );

.

I tried salem's method but the same problem persists.i.e.,during run of the prog, at first if I enter choice#1(for entering data) and then press 'enter', then this 'enter' i.e.,'\n' is taken as input for the name of the commodity and then the prog asks for the company name...........suggest a way out.

[BobS0327]

'\n' is taken as input for the name of the commodity and then the prog asks for the company name...........suggest a way out.

do
    {
        choice=menu();
        // Flush buffer 
        while ((ch = getchar()) != '\n' && ch != EOF);        
        switch(choice)
        {
            case 1:
                ptr=(entry *)malloc(sizeof(entry));
                fpt=fopen("data5.bin","a");

[Salem]

Yeah, you get that if you mix fgets() and scanf().
Use fgets() for EVERYTHING, then use sscanf(), or whatever else seems appropriate.