Sometime recently python3 stopped working, I suspect when it became
patched through to python3.9.

Cygcheck output attached.

Here's some evidence from the command line...
  >: python3.9
  >: echo $?
  127
  >: strace -o /tmp/py.trace python3.9
  strace.exe: error creating process python3.9, (error 2)
  >: echo $?
  1
  >: ls -l /tmp/py.trace
  -rwx------+ 1 ht ht 0 Dec 21 12:30 /tmp/py.trace*
  >: type python3.9
  python3.9 is hashed (/usr/bin/python3.9)
  >: ls -l /usr/bin/python3.9
  -rwxr-xr-x 1 ht ht 9747 Dec  5 12:37 /usr/bin/python3.9*
  >: ldd /usr/bin/python3.9
          ntdll.dll => /c/Windows/SYSTEM32/ntdll.dll (0x7ff99d910000)
          KERNEL32.DLL => /c/Windows/System32/KERNEL32.DLL (0x7ff99be80000)
          KERNELBASE.dll => /c/Windows/System32/KERNELBASE.dll (0x7ff99b020000)
          cygwin1.dll => /usr/bin/cygwin1.dll (0x180040000)
          libpython3.9.dll => /usr/bin/libpython3.9.dll (0x4c63d0000)
          cygintl-8.dll => /usr/bin/cygintl-8.dll (0x3e8760000)
          cyggcc_s-seh-1.dll => /usr/bin/cyggcc_s-seh-1.dll (0x3e8900000)
          cygiconv-2.dll => /usr/bin/cygiconv-2.dll (0x3e8780000)

I tried re-installing python 3.9, no joy.

A further (relate?) oddity, although python3.8 is working:

  >: cygcheck -c python3
  Cygwin Package Information
  Package              Version        Status
  python3              3.8.6-1        OK
  >: cygcheck -c python39
  Cygwin Package Information
  Package              Version        Status
  python39             3.9.9-1        OK
  
  >: python3
  >: echo $?
  127
  >: ls -l /usr/bin/python3 lrwxrwxrwx 1 ht ht 25 Nov 28 13:51 /usr/bin/python3 -> /etc/alternatives/python3*
  >: ls -l /etc/alternatives/python3 lrwxrwxrwx 1 ht ht 18 Dec 21 09:44 /etc/alternatives/python3 -> /usr/bin/python3.9*

Suggestions for how to figure out what's wrong?

ht


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