Mercurial > octave
changeset 11142:3450551f591e
new function, is_valid_file_id
| author | John W. Eaton <jwe@octave.org> |
|---|---|
| date | Sat, 23 Oct 2010 01:50:14 -0400 |
| parents | 224c80da37c5 |
| children | 195cffc2d0a3 |
| files | doc/ChangeLog doc/interpreter/io.txi scripts/ChangeLog scripts/io/is_valid_file_id.m scripts/io/module.mk |
| diffstat | 5 files changed, 51 insertions(+), 0 deletions(-) [+] |
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--- a/doc/ChangeLog Sat Oct 23 13:37:36 2010 +0800 +++ b/doc/ChangeLog Sat Oct 23 01:50:14 2010 -0400 @@ -1,3 +1,8 @@ +2010-10-23 John W. Eaton <jwe@octave.org> + + * interpreter/io.txi (Opening and Closing Files): + Document is_valid_file_id. + 2010-10-21 John W. Eaton <jwe@octave.org> * interpreter/contributors.in: Add Gunnar Farnebäck to the list.
--- a/doc/interpreter/io.txi Sat Oct 23 13:37:36 2010 +0800 +++ b/doc/interpreter/io.txi Sat Oct 23 01:50:14 2010 -0400 @@ -320,6 +320,8 @@ @DOCSTRING(fclose) +@DOCSTRING(is_valid_file_id) + @node Simple Output @subsection Simple Output
--- a/scripts/ChangeLog Sat Oct 23 13:37:36 2010 +0800 +++ b/scripts/ChangeLog Sat Oct 23 01:50:14 2010 -0400 @@ -1,3 +1,8 @@ +2010-10-23 John W. Eaton <jwe@octave.org> + + * io/is_valid_file_id.m: New function. + * io/module.mk (io_FCN_FILES): Add it to the list. + 2010-10-23 Ben Abbott <bpabbott@mac.com> * io/textscan.m, miscellaneous/unimplemented.m, io/module.mk:
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/scripts/io/is_valid_file_id.m Sat Oct 23 01:50:14 2010 -0400 @@ -0,0 +1,38 @@ +## Copyright (C) 2010 John W. Eaton +## +## This file is part of Octave. +## +## Octave is free software; you can redistribute it and/or modify it +## under the terms of the GNU General Public License as published by +## the Free Software Foundation; either version 3 of the License, or (at +## your option) any later version. +## +## Octave is distributed in the hope that it will be useful, but +## WITHOUT ANY WARRANTY; without even the implied warranty of +## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +## General Public License for more details. +## +## You should have received a copy of the GNU General Public License +## along with Octave; see the file COPYING. If not, see +## <http://www.gnu.org/licenses/>. + +## -*- texinfo -*- +## @deftypefn {Function File} {} is_valid_file_id (@var{fid}) +## Return true if @var{fid} refers to an open file. +## @seealso{fopen} +## @end deftypefn + +function retval = is_valid_file_id (fid) + + retval = false; + + if (nargin == 1) + try + [file, mode, arch] = fopen (fid); + retval = ! isempty (file); + end_try_catch + else + print_usage (); + endif + +endfunction