ccc27bdcd2 doc: Clarify -blocksdir usage (Daniel McNally)
Pull request description:
This PR attempts to clarify and correct the `-blocksdir` argument description and default value. `-blocksdir` does not refer to the full path to the actual `blocks` directory, but rather the root/parent directory which contains the `blocks` directory. Accordingly, the default value is `<datadir>` and not `<datadir>/blocks` - this behavior of defaulting to the datadir can also be seen in init.cpp:
```cpp
if (gArgs.IsArgSet("-blocksdir")) {
path = fs::system_complete(gArgs.GetArg("-blocksdir", ""));
if (!fs::is_directory(path)) {
path = "";
return path;
}
} else {
path = GetDataDir(false);
}
```
It also attempts to clarify that only the `.dat` files containing block data are impacted by `-blocksdir`, not the index files.
I believe this would close #12828.
ACKs for commit ccc27b:
hebasto:
utACK ccc27bdcd2d91fe2c023ad004019d5b970f21dbf