The Notes a Program Leaves on One Page
Leave the same private data on one numbered page rather than on the document as a whole.
See It in a Real PDF
The Notes a Program Leaves Itself
A press proof carrying the run on the file, the plate on the page and the ink on the colour bar placed twice. None of it is drawn and no reading software shows it: it is there for the program that wrote it.
Summary
The same as the notes a program leaves in the file for itself, aimed at one page. The press room puts the run on the file and the plate on the page it was set for: the sheet then carries what belongs to the sheet. Nothing of it is drawn, and no reading software shows it.
Technically
Written at the top level of a request, under
"page_private_data"
page_private_data writes the /PieceInfo of one page and the /LastModified beside it, under the private name that entry states. Each entry names the page it is for, counted from one as every page number in a request is, and carries the same three keys the document's own private data carries. Two entries for one page leave the page with the last of them.
Request Schema
-
page_private_data— array, optional, empty by default. -
page_private_data[].page— integer ≥ 1, required. The page the data is for. -
page_private_data[].private_data— object, required.program,modifiedandprivate, the three the document's own private data carries.
Scope: one page. private_data leaves the same on the document itself, and drawings[].private_data on a named drawing.
A Whole Request That Creates a PDF
{
"page_private_data": [
{
"page": 1,
"private_data": {
"program": "PressDesk",
"modified": "2026-09-07T08:15:00+02:00",
"private": "{\"plate\":\"C\",\"screen\":175}"
}
}
],
"standard_fonts": [{ "name": "sans", "face": "helvetica" }],
"items": [
{
"type": "text",
"rect": { "llx": 72, "lly": 700, "urx": 523, "ury": 740 },
"content": ["A proof, and the plate this page was set for underneath it"],
"font": "sans",
"font_size": 12
}
]
}The document as a whole
The Numbers Reading Software Shows A Hundred Letters in a Single File What the Document Says about Itself What the Document Says about Itself, Said Once Text Nobody Can Copy The Notes a Program Leaves in the File for Itself The Data a Program Hangs on a Run of Ink A File Still Readable Decades from Now The Print Standard the Document Claims The Variable Print Standard the Document Claims The Password That Opens It, and What May Be Done with It An Invoice a Person and a Machine Both Read The Address Relative Links Are Read Against The PDF Version the File Declares The Extensions to PDF the File Says It Uses What a Picture Says about Itself, and How It Is Read The Attachments the Document Carries Beside Its Pages Files the Document Names without Carrying The Attachments Shown as a Portfolio Which Attachments a Page Claims Which Attachments a Font Claims The Identity Card a Single Font Carries Which Attachments the Document's Card Claims A Document Card Written Elsewhere The Areas of a Page a Reader Measures In The Identity Card a Single Page Carries The Accessibility Standard the Document Claims The Standards the Finished Document Is Measured Against
Where to Go Next
Every JSON key of a request, in one page The other forty-one settings of a request