ncvalidator(1)

👑 ncvalidator(1) — the vibe check for your netCDF files 💅

okay bestie, imagine a lil utility that just stares at your netCDF file and tells you if it's valid or not. That's ncvalidator, and it lives in the PnetCDF utilities fam. She's simple, she's iconic, and she will absolutely clock a busted header. Let's get into it 🦋

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✨ NAME ✨

ncvalidator — validates a classic netCDF file against CDF file formats 🌸

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✨ SYNOPSIS ✨

ncvalidator [-x] [-t] [-q] [-h] file

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✨ DESCRIPTION ✨

So what she actually does: ncvalidator checks the header of a netCDF file to see whether it conforms to the classic CDF file formats. No cap, that's the whole job. 🎀

If the input file is a valid NetCDF file, she prints a message of successful validation on command-line output, and it looks like this:

File "testfile.nc" is a valid NetCDF file

Otherwise? She prints a NetCDF error message instead. It's giving ✨disappointed✨ but she's still being helpful fr fr.

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✨ OPTIONS ✨

• -x — Repair the null-byte padding in the file header 🩹 The null-byte padding is required by the NetCDF Classic Format Specifications. PnetCDF enforces this requirement, but NetCDF has never enforced it. This option checks the header for locations where null bytes are expected, and replaces them with null bytes if non-null bytes are found. The repaired file is then conformed with the specification and allows both PnetCDF and NetCDF libraries to read the file without reporting error code NC_ENOTNC or NC_ENULLPAD. Noted that this repair is done in place, and users might want to backup the input file first — seriously bestie, back it up 🙈 Once the file is repaired, one may run ncmpidiff command to compare the contents of two files.
• -t — Turn on tracing mode, printing the progress of all successful metadata validation 👀 When an error is detected, the tracing stops at the location of the error found. It's like a live stream of your validation journey 🔥
• -q — Quiet mode — print nothing on the command-line output 🤫 When in quiet mode, users should check exit status. See below in "EXIT STATUS". (She's giving mysterious main character energy, so you have to check the receipts yourself.)
• -h — Print the available command-line options 👑

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✨ EXIT STATUS ✨

An exit status of 0 means the file is conform with the classic CDF file format, and 1 means otherwise. 💖

Heads up on VMS-based system, the exit status values are reversed. Not a drill, not a typo, that's just how it is over there 💀

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✨ SEE ALSO ✨

ncmpidump(1), pnetcdf(3) 🫶

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✨ DATE ✨

July 1, 2026 🌈

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and that's the whole page, periodt 💅 this was the ncvalidator(1) manual out of PnetCDF 1.15.0, printed on 2026-11-02 — go validate something and slay ✨👑🦋