Re: eval doesn't close file descriptor?

[Greg Wooledge]

On Tue, Feb 12, 2013 at 11:07:06AM -0500, Matei David wrote:
> On a different but related note, I hate having to do eval to manipulate an
> fd stored in a variable. Why doesn't 'llfd $x>&-' work, especially since
> 'llfd >&$x' works just fine... so by the time >& is handled, the variable
> substitutions seem to be done already.

      Each redirection that may be preceded by a file descriptor number may
      instead be preceded by a word of the form {varname}.  In this case,
      for each redirection operator except >&- and <&-, the shell will
      allocate a file descriptor greater than 10 and assign it to varname.
      If >&- or <&- is preceded by {varname}, the value of varname defines
      the file descriptor to close.

This was added in Bash 4.1.