structure problems

[Unregistered]

Ok here is my structure...

typedef struct stock_details
{
char stckno[3];
char name[15];
char description[30];
char price[6];
}stock_data;

that i get...
then i use fgets and, fseek to get the input and get rid of any null values... like so:

fgets(stck1.stckno, 2, stdin); //get input
fseek(stdin, 0, SEEK_END); //dicard xtra
fgets(stck1.name,14, stdin);
fseek(stdin, 0, SEEK_END);
fgets(stck1.description, 29, stdin);
fseek(stdin, 0, SEEK_END);
fgets(stck1.price, 5, stdin);
fseek(stdin, 0, SEEK_END);

problem is when i input this into a text file the text is all over the place because it is reading enter keys... any way to get rid of them? oh and i already blanked the variables too... eg stockno has " " entered into it futher up my code...

any help appreciated

[Sy]

ok so i tried this way in the hope of getting rid of any \n's (entrptr and c are poiinters... with c = '\n'

fgets(cus1.name,14, stdin);
entrptr = strchr(cus1.name, c);

if (entrptr)
{
fseek(stdin, 0, SEEK_END);
}

but that doesnt seem to work... am i doing something wrong?

[Sy]

the examples are from similar code... two separate modules, imagine cus1.name is stck1.stckno or something

[Sy]

Well you helpful bunch... i solved it :P

[Sayeh]

Why would you go through all this pain to read/write a structure to disk? Instead of all the fgets, just read and/or write the entire structure _once_ in binary mode?

[Unregistered]

would greatly appreciate ur thoughts on directly reading/writing entire structures directly in binary mode....cheers!

[quzah]

> would greatly appreciate ur thoughts on directly
> reading/writing entire structures directly in binary
> mode....cheers!

Simple stuff:

fread( &toThisStruct, sizeof( struct ThisStruct ), 1, filePointer );

If you're reading into an array, replace '&toThisStruct' with the name of the array, and replace the '1' with the number of structures to read.

fwrite works the same way.

Quzah.

[Sy]

Originally posted by Sayeh
Why would you go through all this pain to read/write a structure to disk? Instead of all the fgets, just read and/or write the entire structure _once_ in binary mode?

because in my project i am creating a customer file of a fixed length... i would use the binary method for something less permanenant like placing an order say... but customers i would rather store on disk

[Sy]

for anyone interested here is the final code... the get_string function is particularly useful because it has teh advanteages og fgets yet it nulls any entere characters... veru useful for output to a text file...

//Add a customer (1.1.1)
//Will be passed a filename (in this case g_filename)
//Returns customer number
//By Simon Taylor

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

void get_string(char*buf, int length);

char cus_file[15]="C:\\test.txt";

typedef struct cus_details
{
int account[6];
char name[16];
char address[61];
char postcode[9];
char tel_no[13];
}cus_data; //can be treaten as a type of variable (cus_data variable_name)

int main(void)
{
//printf("%s\n\n",g_filename); check filename being passed in

char yesno;
FILE*fp;
fp=fopen(cus_file, "a+");

if(fp==NULL)
{
fprintf(stderr, "Could not open or create file");
return 1;
}

do
{
printf("To add a Customer...\n");
printf("\tType Cus_name\n\tAddress\n\tPostcode\n\tTel_No\n\n");

cus_data cus1; //cus1 is my new cusdata variable which has lil ones inside
get_string(cus1.name,15);
get_string(cus1.address,60);
get_string(cus1.postcode,8);
get_string(cus1.tel_no,12);

fwrite(&cus1.name,15,sizeof(char),fp); //the clever bit, write something size of cus1.name to fp
fwrite(&cus1.address, 60,sizeof(char),fp);
fwrite(&cus1.postcode, 8, sizeof(char),fp);
fwrite(&cus1.tel_no, 12, sizeof(char),fp);

printf("Add another customer? Y/N");
scanf("%c%*c", &yesno);

}while (yesno!='n');

fclose(fp);

return 0;
}


void get_string(char*buf, int length) //funtion getin cus name and the lenth
{

char*entrptr; //pointer for the enter character
memset(buf,' ',length); //make the (eg, cus1.name) = as many blanks as in length
fgets(buf,length, stdin); //fill the buffer (eg, cus1.name) up to as many ASCII as in length
entrptr = strchr(buf, '\n'); //if an enter is found point to it

if (entrptr!=NULL) //if the pointer is not null
*entrptr='\0'; //set the char at that location as null
fseek(stdin, 0, SEEK_END); //discard any input past length
}