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POHandling with array of structures in C
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copied!<p>Sorry for long question but I am about to go crazy here.</p> <p>I am trying to write a little simulation of a social network in c language.</p> <p>I'm trying to create an array of structures which each one is a user.</p> <p>For 6 days, I'm trying to write the part that the program adding users and reaching the logs afterwards, and I couldn't. So I'm about to lose my mind over here.</p> <pre><code>struct myStruct { /* This is a global variable */ char *studentName; int *bornYear; char *school; }; </code></pre> <p>then in the main function, I create a pointer such as;</p> <pre><code>struct myStruct** students = malloc (sizeof(struct myStruct )); int counter = 0; /* the counter of students */ </code></pre> <p>by if-else if and switch-case chains, I categorize the commands. when it is asked to add a new user, a realloc the array I created:</p> <pre><code>students = realloc(students, (counter+1) * sizeof (struct students)); students[counter] = adding (*command, counter); counter++; </code></pre> <p>the function is here:</p> <pre><code>struct myStruct adding (char theCommand[], int i){ struct myStruct *q = malloc(sizeof(struct myStruct *)); // I get a warning for this allocation char *irrelevantChar = strtok(theCommand[], ";"); q->studentName = strtok(NULL, ","); q->bornYear= strtok(NULL, ","); q->school= strtok(NULL, ","); return q; </code></pre> <p>I am sure that strtok functions are working right.</p> <p>When I try to reach these structures, the program gives error on run-time (stoppes working on windows, segmentation fault on ubuntu) or I see random irrelevant data etc. I am working with this for 6 days so I have seen lots of errors. But I couldn't find the right way to create and access these structures.</p> <p>In another command situation;</p> <pre><code>"command character" John Smith,George Lucas // names are just for example :) </code></pre> <p>I just wrote the following code for this situation:</p> <pre><code>printf ("\n\n%s", myStruct[0]->school; </code></pre> <p>This is just a random order, just to show that I cannot access it.</p> <p>The output must be "Oxford University" or something. Instead, I get the exactly following output:</p> <pre><code>ge Lucas </code></pre> <p>So some random data. I don't know what is wrong with here either.</p> <p>I must build friendships etc. so I must have access to every single structure I created.</p> <p>Thanks :)</p>

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