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dynamic array ?

hi all

i need a function that returns all the file names contained in a
directory
since the number of files is not known in advance
how should i go about to use "dynamic array" to hold the file names ?

can anyone post some code snippets please?
thanks

Oct 22 '07 #1
4 1587
David d'Angers wrote:
hi all

i need a function that returns all the file names contained in a
directory
since the number of files is not known in advance
how should i go about to use "dynamic array" to hold the file names ?
Look at the manual page for realloc...
can anyone post some code snippets please?
Someone might, but I'm afraid it won't be me.
Oct 22 '07 #2
thanks
you've helped already
i should be looking at dynamic memory allocation

Oct 22 '07 #3
David d'Angers wrote:
hi all

i need a function that returns all the file names contained in a
directory
since the number of files is not known in advance
how should i go about to use "dynamic array" to hold the file names ?

can anyone post some code snippets please?
thanks
One strategy might be to use an array of char *.

char **files = malloc(WHATEVER _INITIAL_SIZE * sizeof *files);

This sets up `files` to point to an array of char * of
WHATEVER_INITIA L_SIZE elements.

Now you can initialise each element in the array to point a block of
char objects to hold each directory entry like this:

files[ctr] = malloc(FILENAME _LENGTH * sizeof **files);

If the number of directory entires is more than WHATEVER_INITIA L_SIZE,
then you can use realloc to expand the array. Be sure to preserve your
old value for files before calling realloc, since it'll return NULL on
failure but will still leave the old block untouched.

char **tmp = realloc(files, NEW_SIZE);
if (tmp != NULL) files = tmp;
/* proceed */

Oct 22 '07 #4
thanks goto santosh with all my heart
i was just feeling confused about the fact that each element in the
array is itself unknown

Oct 22 '07 #5

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