Tukukkk

I'm trying to write a program which can delete a record in file io. The file content is set by default. Now I am trying put my text file content into Array, but there is some trouble happening....

Firstly,it is my default data file content:

1001

eric

1

human

10

70.00

eric

home

arrive





1002 

She

1 

human 

10 

50.00 

she

home 

arrive





1003 

She_eric

2 

human 

10 

120.00 

eric 

home 

arrive

Here is my code:(i am using fscanf putting my text file data into array,you can see it in the middle about open file for read)

#include <stdio.h>

#include <stdlib.h>

struct record{

char recordnum [40];

char itemrecord [40];

char quantity [40];

char weight [40];

char itemname [40];

char catagory [40];

char recipient [40];

char final_destination [40];

char status [40];

};







int main()

{

FILE *fileptr1, *fileptr2, fileptr3;

char filename[40]="record.txt";

char save;

int delete_num, temp ;

char reply;



#define MAX 9

struct record Arr[MAX];



printf("Enter file name: ");

scanf("%s", filename);





do{

temp =1; //reset temp and loop can work below time



//open file in read mode

fileptr1 = fopen(filename, "r");

if (fileptr1== NULL){

printf("open unsuccessful,file not exist"); 

exit(1);

}



save = getc(fileptr1);

while (save != EOF)

{

    printf("%c", save);

    save = getc(fileptr1);

    int i =0;

    for (i=0; i<3 ; i++){



    fscanf(fileptr1,"%s %s %s %s %s %s %s %s %s", Arr[i].recordnum, 

 Arr[i].itemname, Arr[i].itemrecord, Arr[i].catagory, Arr[i].quantity, 

 Arr[i].weight, Arr[i].recipient, Arr[i].final_destination, Arr[i].status 

 ); 



}

}

//rewind

rewind(fileptr1);





printf(" nn Enter record number to be deleted <type 0 = not delete 

anything>:");

fflush(stdin);

scanf("%d", &delete_num);





//open new file in write mode

fileptr2 = fopen("copy.c", "w");

save = getc(fileptr1);

while (save != EOF)

{

    save = getc(fileptr1);

    //except the line to be deleted

    int i ;



    for (i=0;i<3;i++){



    if (temp != delete_num)

    {

        //copy all lines in file replica.c

        putc(save, fileptr2);

}}

}









fclose(fileptr1);

fclose(fileptr2);

remove(filename);

//rename the file replica.c to original name

rename("copy.c", filename);

fflush(stdout);

printf("nThe contents of file after being changed are as follows:n");



fileptr1 = fopen(filename, "r");

save = getc(fileptr1);

while (save != EOF)

{

    printf("%c", save);

    save = getc(fileptr1);

}

fclose(fileptr1); 



fflush(stdin);



printf("nn Delete anther item?<y/n>: ");

scanf("%c",&reply);  







}while(reply=='y' || reply=='Y');

return 0;

}

Sorry for my long code......

Result:

Enter file name:record.txt

10 

Enter record number to be deleted <type 0 = not delete anything>:1001

The contents of file after being changed are as follows:



0000000111

eeerrriiiccc

111

hhhuuummmaaannn

111000

777000...000

eeerrriiiccc

hhhooommmeee

aaarrrrrriiivvveee

and below result same......interesting....

It is not my expected result... i know the word appear three time because of my for loop. However I want my for loop run 3 time , first time include 9record and below..

You're using getc to read characters from the file, but then discarding them. So you're likely to lose meaningful characters. You're also not checking the return value of fscanf to see if it succeeded, leaving the possibility of getting errors without realizing it. You can fix both by getting rid of the getc calls and using the return value of fscanf to control your loop:

while (fscanf(fileptr1,"%39s%39s%39s%39s%39s%39s%39s%39s%39s",

              Arr[i].recordnum, Arr[i].itemname, Arr[i].itemrecord,

              Arr[i].catagory, Arr[i].quantity, Arr[i].weight,

              Arr[i].recipient, Arr[i].final_destination, Arr[i].status) == 9) {

    if (++i >= MAX)

        break;

}

Then, to write the file, you want to delete the record requested, not just a single line. So your best bet is to (re)write the file from scratch using the data you previously read into Arr and leaving out the record you want to delete.