Solved

code fix

Posted on 2000-03-08
6
182 Views
Last Modified: 2010-04-15
help..
somethings wrong w/ this code..
esp on mallocing.

#define MAX 20

typedef struct indexrecord {
   int    index[26];
   long   start;
   long   count;
} indexrecord;

indexrecord *idxrec[MAX];
long wordctr=0;

void readindex(void) {
   FILE *fpidx;
   register int i, j;
   int intvar;
   long longvar;

   fpidx = fopen("index.txt", "r");
   if (!fpidx) {
       printf("error opening file\n");
       exit(1);
   }    
   for (j=0; j<25; j++) {
      idxrec[j] = (indexrecord *) malloc(sizeof(indexrecord));
      for (i=0; i<26; i++) {
         idxrec[j]->index[i] = (int) malloc(sizeof(int));
         idxrec[j]->index[i] = 0;
        }
        idxrec[j]->count = (long) malloc(sizeof(longvar));
        idxrec[j]->start = (long) malloc(sizeof(longvar));
      idxrec[j]->count = 0;
      idxrec[j]->start = 0;
   }

   for (j=0; j<23; j++) {
      for (i=0; i<26; i++) {
         fscanf(fpidx, "%d", &intvar);
         idxrec[j]->index[i] = intvar;
      }
      fscanf(fpidx, "%ld", &longvar);
      idxrec[j]->start = longvar;
        fscanf(fpidx, "%ld", &longvar);
        idxrec[j]->count = longvar;
        wordctr += longvar;
   }
   fclose(fpidx);
}
0
Comment
Question by:ibo
  • 2
  • 2
  • 2
6 Comments
 
LVL 2

Accepted Solution

by:
bbousquet earned 50 total points
Comment Utility
Why are you using mallocs everywhere?

You just need to malloc each indexrecord structure once and store the pointer in your idxrec array. No need to allocate very single member from the structure.

[and don't forget to use free to deallocate the malloc'ed vars]

0
 
LVL 3

Expert Comment

by:terajiv
Comment Utility
Hi ibo,
see the code below
////////////////////////////////////////
for (j=0; j<25; j++) {
      idxrec[j] = (indexrecord *) malloc(sizeof(indexrecord));
      for (i=0; i<26; i++) {
         idxrec[j]->index[i] = (int) malloc(sizeof(int));
         idxrec[j]->index[i] = 0;
  }
  idxrec[j]->count = (long) malloc(sizeof(longvar));
  idxrec[j]->start = (long) malloc(sizeof(longvar));
      idxrec[j]->count = 0;
      idxrec[j]->start = 0;
   }
//////////////////////////////////////////
Here u have already allocated memory to the Structure by Typing
>>idxrec[j] = (indexrecord *) malloc(sizeof(indexrecord));

and after that again ur allocating memory to the same structure elements.

See when u allocate memory to Structure memory is allocated to the Members. So no need to Allocate it Seperately and this is the main cause of ur Problem Remove that and see u will get good Result.

Rajiv
0
 
LVL 2

Expert Comment

by:bbousquet
Comment Utility
terajiv, that is EXACTLY what I just said above.

It is the custom around here to respond to questions with comments. The question asker will then decide which comment better answers his problem/question. That way, the question is not locked for others to answer.

0
How to run any project with ease

Manage projects of all sizes how you want. Great for personal to-do lists, project milestones, team priorities and launch plans.
- Combine task lists, docs, spreadsheets, and chat in one
- View and edit from mobile/offline
- Cut down on emails

 
LVL 3

Author Comment

by:ibo
Comment Utility
sorry terjiv but i have to give the credit to whoever gave the answer first.
comments are answers too.
0
 
LVL 3

Expert Comment

by:terajiv
Comment Utility
Its ok...Actually I should say Sorry...
Anyway
The Imp thing is ur Problem is solved.

So Cheers
Rajiv
0
 
LVL 3

Author Comment

by:ibo
Comment Utility
hi im back..
so what was left was

idxrec[j] = (indexrecord *) malloc(sizeof(indexrecord));

i replaced it with:
*idxrec = (indexrecord *) malloc(sizeof(indexrecord));

but it produced a core dump. it crashed.

sorry i didnt really tried the solution right away.. i just assumed it was the right thing.
actually i had my reason for allocating each element in the structure. i originally programmed this in turbo c, tried this way but didnt work.. so i was able to make it work only by allocating each of the elements. but now in linux it doesnt work.
help pls. im not yet very familiar with unix c.
0

Featured Post

IT, Stop Being Called Into Every Meeting

Highfive is so simple that setting up every meeting room takes just minutes and every employee will be able to start or join a call from any room with ease. Never be called into a meeting just to get it started again. This is how video conferencing should work!

Join & Write a Comment

An Outlet in Cocoa is a persistent reference to a GUI control; it connects a property (a variable) to a control.  For example, it is common to create an Outlet for the text field GUI control and change the text that appears in this field via that Ou…
Preface I don't like visual development tools that are supposed to write a program for me. Even if it is Xcode and I can use Interface Builder. Yes, it is a perfect tool and has helped me a lot, mainly, in the beginning, when my programs were small…
The goal of this video is to provide viewers with basic examples to understand recursion in the C programming language.
The goal of this video is to provide viewers with basic examples to understand opening and reading files in the C programming language.

771 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question

Need Help in Real-Time?

Connect with top rated Experts

10 Experts available now in Live!

Get 1:1 Help Now