`pdfSetLicenseKey`

Category	Licensing
Variants	`pdfSetLicenseKey` (bare / ANSI)

Purpose — Register a license key; a valid key suppresses the trial watermark.

Description — Stores the key on the instance and validates it. The call always returns TRUE (LumasPDF-compatible, including the documented nil-instance pre-create call, which is accepted as a no-op that still succeeds). Validation is real: the key must match the form LUMAS-<body>-<checksum>, where <checksum> is the uppercase 8-hex-digit FNV-1a-32 of <body>. A key that validates sets the instance's licensed flag, which suppresses the trial demo watermark.

Declarations

BOOL32 __stdcall pdfSetLicenseKey(PPDF IPDF, const char* Key);

Delphi

function pdfSetLicenseKey(const IPDF: PPDF; const Key: PAnsiChar): LongBool; stdcall; external 'LumasPdf.dll';

Parameters

Parameter	Type	Description
`IPDF`	`PPDF`	Instance handle, or `NULL` for the pre-create global set.
`Key`	`const char*`	License key string.

Return value — Always TRUE. Do not use the return value to decide whether the key was accepted — query pdfIsLicensed instead.

Remarks — Because success is unconditional (matching the reference ABI), the only reliable acceptance signal is pdfIsLicensed after this call. Set the key immediately after pdfNewPDF, before opening output, so the watermark decision is made correctly for the whole document.

Example — Delphi (production)

Delphi

var P: PPDF;
begin
  P := pdfNewPDF;
  try
    pdfSetLicenseKey(P, 'LUMAS-ACME-0001-1A2B3C4D');
    if not pdfIsLicensed(P) then
      Writeln('WARNING: running unlicensed — output will be watermarked');
    // ... build document ...
  finally
    pdfDeletePDF(P);
  end;
end;

See also — pdfIsLicensed

C# (P/Invoke)

wrappers/dotnet/LumasPdf.cs

[return: MarshalAs(UnmanagedType.Bool)]

Area

Core SDK