Hey all,
I searched the archives and looked at some of the code in SVN, but I'm still unsure how to do this.
I have a nested for loop that grabs the config options from the PTP camera. The length depends on the camera and its mode.
How can I append each name to a list suitable to be used by outlet_list?
Anyone keeping a collection of PD C external snippets?
Thanks, B.
B. Bogart wrote:
Hey all,
I searched the archives and looked at some of the code in SVN, but I'm still unsure how to do this.
I have a nested for loop that grabs the config options from the PTP camera. The length depends on the camera and its mode.
How can I append each name to a list suitable to be used by outlet_list?
choice 1 (if maximum length is known):
allocate t_atom out[MAX_LENGTH] on the stack (as a normal variable). set argc to the actual length.
choice 2 (if maximum length is not known):
loop through once to get the length malloc() sufficient space loop through again to copy the data send to outlet free() the space
choice 3 (an alternative):
send each config option to the outlet separately (may be more useful than having to parse a list later?)
Claude
On Sat, 21 Mar 2009, Claude Heiland-Allen wrote:
B. Bogart wrote:
I have a nested for loop that grabs the config options from the PTP camera. The length depends on the camera and its mode.
choice 1 (if maximum length is known): choice 2 (if maximum length is not known): choice 3 (an alternative):
choice 4: malloc() just what you need, and then realloc() for any subsequent growth.
choice 5: malloc() some size, keep track of the size allocated, keep track of the size used, realloc() only when needed, by increasing the size allocated by some percentage.
The latter is how many resizable arrays work in various languages. It seems like choice #4 works fast, as it is used by much of Pd without taking much time, but there's no real guarantee that calling realloc() that often should be that fast (and I think that Pd's internals are just being lucky with it). Anyhow, for just a set of camera options, it doesn't matter at all, it could be pretty much any speed.
_ _ __ ___ _____ ________ _____________ _____________________ ... | Mathieu Bouchard - tél:+1.514.383.3801, Montréal, Québec
Why not just create a binbuf object, append all the atoms to it, and then extract the length and atoms vector...
t_atom a; t_binbuf b = binbuf_new(); while(more_data) { SETSYMBOL(&a, camera_data); binbuf_add(b, 1, &a); } outlet_anything(x -> x_obj.ob_outlet, &s_list, binbuf_getnatom(b), binbuf_getvec(b)); binbuf_free(b);
Mike
On Fri, Mar 20, 2009 at 6:07 PM, B. Bogart ben@ekran.org wrote:
Hey all,
I searched the archives and looked at some of the code in SVN, but I'm still unsure how to do this.
I have a nested for loop that grabs the config options from the PTP camera. The length depends on the camera and its mode.
How can I append each name to a list suitable to be used by outlet_list?
Anyone keeping a collection of PD C external snippets?
Thanks, B.
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B. Bogart -
Claude Heiland-Allen -
Mathieu Bouchard -
Mike McGonagle