Updating TexLive/2023

[Rich Shepard]

I just discovered a glitch in my shell script run from within /etc/cron.d/:
I hadn't specified ./tlmgr and ./fmtutil-sys, only the file names.

Having fixed that I ran ./tlmgr update --self --all and it failed:
running mktexlsr ...

tlmgr: mktexlsr failed (status -1), output:

Can't exec "kpsewhich": No such file or directory at ./tlmgr line 906.
Use of uninitialized value $TEXMFSYSVAR in scalar chomp at ./tlmgr line 906.
Can't exec "kpsewhich": No such file or directory at ./tlmgr line 907.
Use of uninitialized value $TEXMFSYSCONFIG in scalar chomp at ./tlmgr line 907.
Can't exec "kpsewhich": No such file or directory at ./tlmgr line 908.
Use of uninitialized value $TEXMFLOCAL in scalar chomp at ./tlmgr line 908.
Can't exec "kpsewhich": No such file or directory at ./tlmgr line 909.
Use of uninitialized value $TEXMFDIST in scalar chomp at ./tlmgr line 909.
Use of uninitialized value $TEXMFDIST in concatenation (.) or string at ./tlmgr line 920.
Can't exec "kpsewhich": No such file or directory at /usr/local/texlive/2023/tlpkg/TeXLive/TLUtils.pm line 3514.
Use of uninitialized value $tmfsysconf in scalar chomp at /usr/local/texlive/2023/tlpkg/TeXLive/TLUtils.pm line 3514.
Use of uninitialized value $tmfsysconf in concatenation (.) or string at /usr/local/texlive/2023/tlpkg/TeXLive/TLUtils.pm line 3515.
Cannot open /web2c/updmap.cfg for writing: No such file or directory at /usr/local/texlive/2023/tlpkg/TeXLive/TLUtils.pm line 3661.

When I look at line 906 and following, tlmgr it seems to be where it should
be:
   chomp(my $TEXMFSYSVAR = `kpsewhich -var-value=TEXMFSYSVAR`);
   chomp(my $TEXMFSYSCONFIG = `kpsewhich -var-value=TEXMFSYSCONFIG`);
   chomp(my $TEXMFLOCAL = `kpsewhich -var-value=TEXMFLOCAL`);
   chomp(my $TEXMFDIST = `kpsewhich -var-value=TEXMFDIST`);

How do I fix this?

TIA,

Rich