contrib/chg/procutil.h

packaging: update keyring on Windows to avoid spurious stacktraces

When challenged for a network password, this would spew on Windows before it
actually used the stored password:

```
Error initializing plugin EntryPoint(name='libsecret', value='keyring.backends.libsecret', group='keyring.backends').
Traceback (most recent call last):
  File "keyring.backend", line 198, in _load_plugins
    init_func = ep.load()
  File "importlib.metadata", line 77, in load
    module = import_module(match.group('module'))
  File "importlib", line 127, in import_module
    return _bootstrap._gcd_import(name[level:], package, level)
  File "<frozen importlib._bootstrap>", line 1030, in _gcd_import
  File "<frozen importlib._bootstrap>", line 1007, in _find_and_load
  File "<frozen importlib._bootstrap>", line 984, in _find_and_load_unlocked
ModuleNotFoundError: No module named 'keyring.backends.libsecret'
Error initializing plugin EntryPoint(name='macOS', value='keyring.backends.macOS', group='keyring.backends').
Traceback (most recent call last):
  File "keyring.backend", line 198, in _load_plugins
    init_func = ep.load()
  File "importlib.metadata", line 77, in load
    module = import_module(match.group('module'))
  File "importlib", line 127, in import_module
    return _bootstrap._gcd_import(name[level:], package, level)
  File "<frozen importlib._bootstrap>", line 1030, in _gcd_import
  File "<frozen importlib._bootstrap>", line 1007, in _find_and_load
  File "<frozen importlib._bootstrap>", line 984, in _find_and_load_unlocked
ModuleNotFoundError: No module named 'keyring.backends.macOS'
```

We're kinda threading a needle here because the next version of `keyring`
(currently at 23.7.0) requires `importlib-metadata` 3.6+, which PyOxidizer 0.22
doesn't support[1].

[1] https://github.com/indygreg/PyOxidizer/issues/609

/*
 * Utilities about process handling - signal and subprocess (ex. pager)
 *
 * Copyright (c) 2011 Yuya Nishihara <[e-mail]>
 *
 * This software may be used and distributed according to the terms of the
 * GNU General Public License version 2 or any later version.
 */

#ifndef PROCUTIL_H_
#define PROCUTIL_H_

#include <unistd.h>

void restoresignalhandler(void);
void setupsignalhandler(pid_t pid, pid_t pgid);

pid_t setuppager(const char *pagercmd, const char *envp[]);
void waitpager(void);

#endif /* PROCUTIL_H_ */