terminology - C programming , need help understanding some concept -

this simple program have done in c , works fine don't understand terminology:

instead of list[list_size] = strdup(file) do:

1. char*test=file , strcpy(list[list_size],test). segmentation fault.

2. char*test=malloc(sizeof(char)*max_filename_len+1) , test=file andstrcpy(list[list_size],test). segmentation fault.

3. or strcpy(list[list_size],file). segmentation fault.

     # include < stdio.h >    # include < string.h >    # define max_list_size 1000   # define max_filename_len 128    int main() {   file * infile;   char * list[max_list_size],   file[max_filename_len + 1];   size_t list_size = 0;   infile = popen("ls", "r");    if (infile != null) {        while ((list_size < max_list_size) &&(fscanf(infile, "%s", file) == 1)) {            list[list_size] = strdup(file);            list_size++;            puts(file);       }   }   pclose(infile);   return 0; 

   }

it great if help.

1. the non-standard strdup function 2 things: allocates dynamic memory , copies string. same thing calling malloc followed call strcpy (which why strdup 100% superfluous function).

   when strcpy(list[list_size],test), list isn't pointing @ allocated memory - pointing @ random memory location anywhere in memory. try copy data random location , crash.

2. you allocate memory , point @ test. forget memory when let test point @ file instead, have created memory leak. , once have done that, same bug in 1, since variables test , file have nothing list.

3. same bug in 1 , 2.

i advise studying pointers , arrays bit more before diving dynamic memory allocation , string handling.