Hi,

If I understand the following source code snippet correctly, the mongo shell will not write the history file if the process is non-interactive but ::shellHistoryDone() is registered as a shutdown task at the very beginning of _main.

//  mongo/src/mongo/shell/dbshell.cpp
int _main(int argc, char* argv[], char** envp) {
    registerShutdownTask([] {
        ...
        ::killOps();
        ::shellHistoryDone();
    });
    ...
    if (shellGlobalParams.files.size() == 0 && shellGlobalParams.script.empty())
        shellGlobalParams.runShell = true;
    ...
    if (shellGlobalParams.runShell) {
        ...
        shellHistoryInit();
        while (1) {...}

        shellHistoryDone();
    }
    ...
}

As a result: if a non-interactive mongo shell aborts, it will try to save history and report error [main] Error saving history file: FileOpenFailed: Unable to open() file : No such file or directory because the history file name is empty.

I understand that mongo shell will continue working and this error message can actually serve as an indication that the non-interactive mongo shell aborts. However, I found some were confused by the error. Therefore, I'd suggest either move registering ::shellHistoryDone() as a shutdown task into the interactive loop if (shellGlobalParams.runShell) or skip linenoiseHistorySave in shellHistoryDone() if the history file path is empty.

Regards,
Lungang