[tex-live] fmtutil: can't enable/disable formats

[Ken Brown]

I'm having problems with fmtutil on Cygwin.  Since no one else has 
reported this, I assume it's a local problem.  But I'm not literate in 
Perl, so I hope someone can help me track this down.  I'm using version 
r37190 of fmtutil.  Here's what happens when I try to disable a format:

$ fmtutil-sys --disablefmt pdftex
fmtutil: fmtutil is using the following fmtutil.cnf files (in precedence 
order):
fmtutil:   /usr/local/texlive/2015/texmf-config/web2c/fmtutil.cnf
fmtutil:   /usr/local/texlive/2015/texmf-dist/web2c/fmtutil.cnf
fmtutil: fmtutil is using the following fmtutil.cnf file for writing 
changes:
fmtutil:   /usr/local/texlive/2015/texmf-config/web2c/fmtutil.cnf
Use of uninitialized value $fmtname in split at 
/usr/local/texlive/2015/bin/x86_64-cygwin/fmtutil line 680.
Use of uninitialized value $fmt in hash element at 
/usr/local/texlive/2015/bin/x86_64-cygwin/fmtutil line 695.
Use of uninitialized value $fmt in concatenation (.) or string at 
/usr/local/texlive/2015/bin/x86_64-cygwin/fmtutil line 707.
fmtutil [WARNING]: Format  is not defined.
fmtutil [WARNING]: Cannot (de)activate it.


If I disable the format by editing 
/usr/local/texlive/2015/texmf-config/web2c/fmtutil.cnf and then try to 
enable it, I get the following:

$ fmtutil-sys --enablefmt pdftex
fmtutil: fmtutil is using the following fmtutil.cnf files (in precedence 
order):
fmtutil:   /usr/local/texlive/2015/texmf-config/web2c/fmtutil.cnf
fmtutil:   /usr/local/texlive/2015/texmf-dist/web2c/fmtutil.cnf
fmtutil: fmtutil is using the following fmtutil.cnf file for writing 
changes:
fmtutil:   /usr/local/texlive/2015/texmf-config/web2c/fmtutil.cnf
$VAR1 = {
   'order' => [
     '/usr/local/texlive/2015/texmf-config/web2c/fmtutil.cnf',
     '/usr/local/texlive/2015/texmf-dist/web2c/fmtutil.cnf'
   ],
   'fmtutil' => {
     '/usr/local/texlive/2015/texmf-dist/web2c/fmtutil.cnf' => {
       'formats' => {
         'mllatex' => {
           'pdftex' => {
             'hyphen' => 'language.dat',
             'status' => 'enabled',
             'args' => '-translate-file=cp227.tcx -mltex *mllatex.ini',
             'line' => 99

[many more lines removed]

       }
     },
     'cslatex' => {
       'pdftex' => {
         'hyphen' => '-',
         'status' => 'enabled',
         'args' => '-etex cslatex.ini',
         'origin' => 
'/usr/local/texlive/2015/texmf-config/web2c/fmtutil.cnf'
       }
     }
   },
   'changes_config' => 
'/usr/local/texlive/2015/texmf-config/web2c/fmtutil.cnf'
};
Undefined subroutine &main::save_fmtutil called at 
/usr/local/texlive/2015/bin/x86_64-cygwin/fmtutil line 655.


Thanks in advance for any help anyone can offer.

Ken

P.S. As far as I can tell, fmtutil works fine for actually creating 
formats.  For example, 'fmtutil-sys --all' and 'fmtutil-sys --byfmt 
pdftex' do create formats.  It's only enabling and disabling that are 
not working for me.

P.P.S.  I've tried both perl-5.14.3 and perl-5.22.0, with the same results.