JSON output is empty in rare cases (smartctl-nc)

[Eaton Zveare]

I received a report from a user that basically indicates the JSON output from smartctl is completely empty. No opening/closing brackets or any other text is output to the command line.

Example command:

smartctl-nc --device={DeviceType} --info --get=security --json pd{PhysicalDeviceNum}

This is on Windows 11. I've reviewed the smartctl code, but can't find any clues. This is also a very isolated case and the first time I have seen it, so it may be some system configuration problem, but am hoping someone could point me in the right direction in diagnosing this.

Also, the non-JSON commands output without issue. This is strictly JSON related.

[Christian Franke]

smartctl-nc output is only available if redirected. Try for example:
smartctl-nc ... | more

See the FAQ for the differences between smartctl-nc vs. smartctl.

[Eaton Zveare]

I should clarify that I am indeed redirecting the output, so the usage is correct, and it works for 99% of users. Not sure why it's tripping up in this one case - any ideas?

[Christian Franke]

• Does it only fail with smartctl-nc.exe or also with smartctl.exe?
• Does the problem persist if --get=security is removed?
• Redirect stderr to a file (2>error.txt) and check its contents.
• Try to run from Cygwin or MSYS2 "Terminal" (aka mintty) if available.

[Eaton Zveare]

Sorry for the delay. I have now confirmed that using the non nc version of smartctl fixes the problem. I will just use that version now, so no action is required here. Thanks for the support!