DynaPDF Manual - Page 560

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Function Reference

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Thread-safety is guaranteed for every PDF instance but it is not allowed to call functions of one

instance in different threads.

If a PDF instance is no longer needed then it must be deleted with DeletePDF().

Remarks:

This function is automatically called in the wrapper classes for Visual Basic, Visual Basic .Net, C#,

and Delphi. There is no need to create PDF instances manually when using these programming

languages.

C/C++ developers must create a PDF instance before a DynaPDF function can be executed.

OpenImportBuffer

Syntax:

SI32 pdfOpenImportBuffer(

const PPDF* IPDF,

// Instance pointer

const void* Buffer,

// Pointer to PDF file

UI32 BufSize,

// Buffer length in bytes

TPwdType PwdType,

// Kind of password and flags (see below)

const char* Password) // Password to decrypt the file

typedef enum

{

ptOpen

= 0, // Open password

ptOwner

= 1, // Owner password

ptForceRepair = 2, // See description below

ptDontCopyBuf = 4

// If set, the buffer is not copied

}TPwdType;

The function opens an external PDF file like OpenImportFile() but accepts a file buffer as input.

The function supports the additional flag ptDontCopyBuf to specify whether the import buffer

should be copied to an internal buffer or not.

If the flag ptDontCopyBuf is absent then DynaPDF creates a copy of the input buffer before it will be

accessed. The original buffer should be released immediately after the function returns in this case.

The internal copy of the file buffer will be released when CloseImportFile() is called, when loading

another PDF file, or when the PDF file in memory is closed.

If the flag ptDontCopyBuf is set, then the function works directly with the source buffer without

creating a copy of it. This reduces the memory usage and improves the processing speed due to the

unnecessary copy action. However, the caller must make sure that the buffer exist until

CloseImportFile() is called. When finish, call first CloseImportFile() and then release the input

buffer.

How to keep multiple memory based PDF files open?

It is also possible to hold more than one memory based PDF file simultaneously in memory. This is

the case if the flag if2UseProxy is set and if CloseImportFile() was not called before opening the next

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