shell.system() can't find system commands, giving error codes 1 and 127

[davidm-ro]

macOS 15.5. A standard Unix system command, nohup, is present:

$ nohup
usage: nohup [--] utility [arguments]

So definitely there.

However when I try to run it using shell.system(), I get errors. This includes using which to find it.

Script:

log("Testing nohup command availability...");
try {
    var result = shell.system("nohup echo 'test' > ./_train-test.txt", ".");
    log("Result: " + result);
    log("Expected: Should create file successfully");
} catch (e) {
    log("Error: " + e);
    log("Note: nohup should be available in standard Unix PATH");
}

log("Testing which nohup...");
try {
    var result = shell.system("which nohup", ".");
    log("Result: " + result);
    log("Expected: Should show path to nohup");
} catch (e) {
    log("Error: " + e);
}

log("Testing direct path to nohup...");
try {
    var result = shell.system("/usr/bin/nohup echo 'test'", ".");
    log("Result: " + result);
    log("Expected: Should work with full path");
} catch (e) {
    log("Error: " + e);
}

Expected vs Observed

1. Should create the file in the same folder, _train-test.txt, with 'test' inside it. Instead, there is no file and I get Failed with error code: 127.
2. Should print where nohup is found, ie for me, /usr/bin/nohup. Instead, I get Failed with error code: 1.
3. It should write something to console; instead, I get Failed with error code: 127