Re: new function: textscan.m

[John W. Eaton]

On 23-Oct-2010, Ben Abbott wrote:

| Regarding a is_valid_file_id() function, I like the idea. Can this
| be done as an m-file? 

We could check that a value is a scalar integer >= 0 in a .m file.
But would it also be useful to know whether the file ID refers to an
open file?  If so, then I think the function will have to be built
in, and it should be pretty easy to add something to the
octave_stream_list class to do the work.  Or should we allow invalid
file IDs and just wait for reading/writing to fail?

jwe