init_error.patch: modify Py_Initialize() to exit with exit(1) instead of abort(), to not call the sytem fault handler (ex: dump a coredump on Linux, or open a popup on Windows).
The patch calls also initsigs() before initfsencoding(), because initfsencoding() may call Python code (encodings implemented in Python).
Example with gdb (to simulate a CTRL+c during Python startup):
$ gdb ./python
(gdb) b initfsencoding
(gdb) run
Breakpoint 1, initfsencoding (interp=0x971420) at Python/pythonrun.c:972
(gdb) signal SIGINT
(gdb) cont
Python initialization error: Unable to get the locale encoding
Traceback (most recent call last):
File "<frozen importlib._bootstrap>", line 2152, in _find_and_load
KeyboardInterrupt
[Inferior 1 (process 15566) exited with code 01]
The process exited with exit code 1, not with SIGABRT.