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POstrcpy crash with char *[] (ARGV Structure)
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copied!<p>I have a problem with the c function 'strcpy' that I have not been able to figure out.</p> <p>it involves copying to a char *[] like Argv (but not actually Argv). I can copy out of the structure but not in. But only if I initially declare the entire Argv Structure in a single go.</p> <p>I assume that a <code>char *[]</code> is and array of <code>char*</code>.</p> <p>Here is a simple demo program of the issue:</p> <pre><code>#include <stdio.h> #include <stdlib.h> #include <string.h> char FN[]="BBBB"; char *TL[]={ "a0 ", "a1 ", "a2 ", "a3 ", "a4 ", "a5 "}; char BN[]="c1 "; char N0[]="N0 "; char N1[]="N1 "; char N2[]="N2 "; char N3[]="N3 "; char N4[]="N4 "; char N5[]="N5 "; char* TD[6]; int main ( int argc, char *argv[] ) { // FN is a pointer to an array of chars // BN is the same //TL is an array of pointers (that each point to an array of chars) //TL[1] is thus a pointer to an array of chars //TL is the same structure as Argv //TD is the same structure as Argv (but built up from parts) // but is spread out across the globals and the main func. // thus less easy to read and understand then TL. //TL[i], TD[i], and BN are initially allocated significantly larger than FN // to remove the worry of overruns. //copy "a1 \0" into the space held by "c1 " strcpy(BN,TL[1]); //works //copy "BBBB\0" into the space held by "c1 " strcpy(BN,FN); //works TD[0]=N0; TD[1]=N1; TD[2]=N2; TD[3]=N3; TD[4]=N4; TD[5]=N5; //copy "BBBB\0" into the space held by "a1 " strcpy(TD[1],FN); //works //copy "BBBB\0" into the space held by "a1 " //strcpy(TL[1],FN); //dies } </code></pre>

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