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POcant assign values to file variable
 

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    <p>im quite new to C, and im trying to populate a file wide array variable with the results of a function, heres a simple code sample to show what i mean, can anyone point me in the direction of why this doesnt work?</p> <pre><code>#include &lt;sys/types.h&gt; #include &lt;dirent.h&gt; #include &lt;regex.h&gt; #include &lt;stdio.h&gt; #include &lt;gtk/gtk.h&gt; #include &lt;string.h&gt; #include &lt;unistd.h&gt; #include &lt;pwd.h&gt; static gchar *external_names; void directories(int arraylength, gchar internal_names[][100]){ int n; for (n = 0; n &lt; arraylength; n++) { strcpy(external_names[n], internal_names[n]); } for (n = 0; n &lt; arraylength; n++) { printf("%s internal with %s external\n",internal_names[n], external_names[n]); } } void main() { gchar anotherarray[10][100]; directories(10, anotherarray); } </code></pre> <p>[EDIT] latest code</p> <pre><code>#include &lt;sys/types.h&gt; #include &lt;dirent.h&gt; #include &lt;regex.h&gt; #include &lt;stdio.h&gt; #include &lt;gtk/gtk.h&gt; #include &lt;string.h&gt; #include &lt;unistd.h&gt; #include &lt;pwd.h&gt; static gchar *external_names[100]; void directories(int arraylength, gchar internal_names[][100]){ int n = 0; //gchar external_names[arraylength][100]; for (n = 0; n &lt; arraylength; n++) { printf("%s %i\n","before", n); strcpy(external_names[n], internal_names[n]); printf("%s %i\n","after", n); } } void main() { int n; gchar anotherarray[10][100]; for (n = 0; n &lt; 10; n++) { strcpy(anotherarray[n],"test"); } directories(10, anotherarray); for (n = 0; n &lt; 10; n++) { printf("%s internal with %s external\n",anotherarray[n], external_names[n]); } } </code></pre>
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    1. COYou're writing to an indeterminate address in memory through that pointer; not a file. Use the FILE apis form the C runtime library, starting with [`fopen()`](http://en.cppreference.com/w/c/io/fopen), [`fprintf()`](http://en.cppreference.com/w/c/io/fprintf), and [`fwrite()`](http://en.cppreference.com/w/c/io/fwrite), etc. That will hopefully get you started.
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    2. COYou can't use the value of a variable until you assign it one. You use `external_names` (in this code: `strcpy(external_names[n], internal_names[n]);`) before you assign it any value.
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    3. COim not trying to write to a file, just a file wide(static) variable, does 'strcpy(external_names[n], internal_names[n]);)' not assign the value of internal_names[n] to the external array?
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