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POWriting an array of structs to a binary file in C
 

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  1. POWriting an array of structs to a binary file in C
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    <p>I have an array of structs I would like to write to a binary file. I have a write.c program and a read.c program. The write.c program seems to be working properly but when I run the read.c program I get a segmentation fault. I'm new to C so It would be great if someone could look over my code for any obvious errors. I promise it's not too long :)</p> <p>write.c:</p> <pre><code>#include &lt;stdlib.h&gt; #include &lt;stdio.h&gt; struct Person { char f_name[256]; char l_name[256]; int age; }; int main(int argc, char* argv[]) { struct Person* people; int people_count; printf("How many people would you like to create: "); scanf("%i", &amp;people_count); people = malloc(sizeof(struct Person) * people_count); int n; for (n = 0; n &lt; people_count; n++) { printf("Person %i's First Name: ", n); scanf("%s", people[n].f_name); printf("Person %i's Last Name: ", n); scanf("%s", people[n].l_name); printf("Person %i's Age: ", n); scanf("%i", &amp;people[n].age); } FILE* data; if ( (data = fopen("data.bin", "wb")) == NULL ) { printf("Error opening file\n"); return 1; } fwrite(people, sizeof(struct Person) * people_count, 1, data); fclose(data); return 0; } </code></pre> <p>read.c:</p> <pre><code>#include &lt;stdlib.h&gt; #include &lt;stdio.h&gt; struct Person { char f_name[256]; char l_name[256]; int age; }; int main(int argc, char* argv[]) { FILE* data; if ((data = fopen("data.bin", "rb")) == NULL) { printf("Error opening file\n"); return 1; } struct Person* people; fread(people, sizeof(struct Person) * 1/* Just read one person */, 1, data); printf("%s\n", people[0].f_name); fclose(data); return 0; } </code></pre> <p>Thanks for the help!</p>
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    1. COHow many times a day does this question get asked? There should be a 'C' FAQ that will allow us to point to the answer rather than spending the time writing all this down time after time after time......
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