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POC - struct problems - writing
 

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  1. POC - struct problems - writing
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    <p>I'm making a program in C, and I'mm having some troubles with memory, I think.</p> <p>So my problem is: I have 2 functions that return a struct. When I run only one function at a time I have no problem whatsoever. But when I run one after the other I always get an error when writting to the second struct.</p> <p>Function <code>struct item* ReadFileBIN(char *name)</code> -- reads a binary file. <code>struct tables* getMesasInfo(char* Filename)</code> -- reads a text file.</p> <p>My code is this:</p> <pre><code>#include "stdafx.h" #include &lt;stdio.h&gt; #include &lt;stdlib.h&gt; #include &lt;string.h&gt; #include &lt;time.h&gt; int numberOfTables=0; int numberOfItems=0; //struct tables* mesas; //struct item* Menu; typedef struct item{ char nome[100]; int id; float preco; }; typedef struct tables{ int id; int capacity; bool inUse; }; struct tables* getMesasInfo(char* Filename){ struct tables* mesas; char *c; int counter,numberOflines=0,temp=0; char *filename=Filename; FILE * G; G = fopen(filename,"r"); if (G==NULL){ printf("Cannot open file.\n"); } else{ while (!feof(G)){ fscanf(G, "%s", &amp;c); numberOflines++; } fclose(G); } /* Memory allocate for input array */ mesas = (struct tables *)malloc(numberOflines* sizeof(struct tables*)); counter=0; G=fopen(filename,"r"); while (!feof(G)){ mesas[counter].id=counter; fscanf(G, "%d", &amp;mesas[counter].capacity); mesas[counter].inUse= false; counter++; } fclose(G); numberOfTables = counter; return mesas; } struct item* ReadFileBIN(char *name) { int total=0; int counter; FILE *ptr_myfile; struct item my_record; struct item* Menu; ptr_myfile=fopen(name,"r"); if (!ptr_myfile) { printf("Unable to open file!"); } while (!feof(ptr_myfile)){ fread(&amp;my_record,sizeof(struct item),1,ptr_myfile); total=total+1; } numberOfItems=total-1; Menu = (struct item *)calloc(numberOfItems , sizeof(struct item)); fseek(ptr_myfile, sizeof(struct item), SEEK_END); rewind(ptr_myfile); for ( counter=1; counter &lt; total ; counter++) { fread(&amp;my_record,sizeof(struct item),1,ptr_myfile); Menu[counter] = my_record; printf("Nome: %s\n",Menu[counter].nome); printf("ID: %d\n",Menu[counter].id); printf("Preco: %f\n",Menu[counter].preco); } fclose(ptr_myfile); return Menu; } int _tmain(int argc, _TCHAR* argv[]) { struct item* tt = ReadFileBIN("menu.dat"); struct tables* t = getMesasInfo("Capacity.txt"); getchar(); }** </code></pre> <p>the error that im getting is : </p> <p>"Unhandled exception at 0x00411700 in test.exe: 0xC0000005: Access violation writing location 0x00000000."</p> <p>in "Menu[counter] = my_record;"</p> <p>Thanks in advance. </p>
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    1. This table or related slice is empty.
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    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
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    1. This table or related slice is empty.
    1. COWhat is the error do you get?
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      1. POC - struct problems - writing
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