The Close command closes a file that has been opened with FileTools[Compressed][Open].

$\mathrm{file}≔\mathrm{FileTools}\left[\mathrm{TemporaryFilename}\right]\left(\mathrm{cat}\left(\mathrm{FileTools}\left[\mathrm{TemporaryDirectory}\right]\left(\right)\,\mathrm{kernelopts}\left(\mathrm{dirsep}\right)\,''GZtest-''\right)\right)$

$\mathrm{file}≔''/tmp/mpldoc17/GZtest-yYoYxV9R''$

$\mathrm{fd}≔\mathrm{FileTools}\left[\mathrm{Compressed}\right]\left[\mathrm{Open}\right]\left(\mathrm{file}\right)$

$\mathrm{fd}≔8294608$

$\mathrm{FileTools}\left[\mathrm{Compressed}\right]\left[\mathrm{Close}\right]\left(\mathrm{fd}\right)$

$0$

$\mathrm{FileTools}\left[\mathrm{Compressed}\right]\left[\mathrm{Open}\right]\left(\mathrm{file}\right)$

$8294608$

$\mathrm{FileTools}\left[\mathrm{Compressed}\right]\left[\mathrm{Close}\right]\left(\mathrm{file}\right)$

$0$

$\mathrm{FileTools}\left[\mathrm{Compressed}\right]\left[\mathrm{Close}\right]\left(\mathrm{file}\right)$

Error, (in FileTools:-Compressed:-Close) invalid input: /tmp/mpldoc17/GZtest-yYoYxV9R does not refer to an open file

The FileTools[Compressed][Close] command was introduced in Maple 16.

For more information on Maple 16 changes, see Updates in Maple 16.