This is the "C" level API of RecPDFAPI. RecPDF API-level of CSDK is supported on: Windows, Linux, Mac OS X. More...

Typedefs
typedef struct tagRPDF_DOC *	RPDF_DOC
	Handle of a PDF document.
typedef struct tagRPDF_OPERATION *	RPDF_OPERATION
	Handle of a PDF operation.
typedef struct tagRPDF_FILEENUMERATOR *	RPDF_FILEENUMERATOR
	Handle of an enumerator for the PDF documents taking part in a PDF operation.
Enumerations
enum	RPDF_ENCRYPTION { ENC_NO, ENC_RC4, ENC_AES }
	Encryption type of a PDF file. More...
enum	RPDF_RESTRICTIONS { PSR_NO_PRINT = 0x00000100, PSR_NO_HIPRINT = 0x00000200, PSR_NO_COPY = 0x00000400, PSR_NO_EXTRACT_TEXT = 0x00000800, PSR_NO_EXTRACT_PAGES = 0x00001000, PSR_NO_CHANGE = 0x00002000, PSR_NO_ASSEMBLE = 0x00004000, PSR_NO_ACROFORM = 0x00008000, PSR_NO_ANNOT = 0x00010000 }
	PDF security restriction flags. More...
enum	RPDF_ROTATION { PDFROT_NO = 0, PDFROT_LEFT, PDFROT_RIGHT, PDFROT_HALFTURN }
	Page rotation. More...
enum	PDF_Version
	PDF version.
enum	PDFA_Version
	PDFA version.
Functions
RECERR PDFASMAPI	rPdfInit (void)
	Initialize the RecPDF.
RECERR PDFASMAPI	rPdfQuit (void)
	Uninitialize the RecPDF.
RECERR PDFASMAPI	rPdfOpen (LPCTSTR pFileName, LPCTSTR password, RPDF_DOC *handle)
	Open a PDF file.
RECERR PDFASMAPI	rPdfCompact (LPCTSTR pInFileName, LPCTSTR pOutFileName)
	Compact a PDF document.
RECERR PDFASMAPI	rPdfClose (RPDF_DOC handle)
	Close a PDF document.
RECERR PDFASMAPI	rPdfGetOp (RPDF_DOC handle, RPDF_OPERATION *ophandle)
	Get the PDF operation assigned to a PDF document.
RECERR PDFASMAPI	rPdfGetPath (RPDF_DOC handle, LPTSTR buffer, size_t buflen)
	Get the path of the PDF document.
RECERR PDFASMAPI	rPdfFileHasText (RPDF_DOC handle, size_t position, bool *bHasText)
	Check if a page of the PDF document does have or doesn't have searchable text.
RECERR PDFASMAPI	rPdfGetPageCount (RPDF_DOC handle, size_t *pnPages)
	Get the page count of a PDF document.
RECERR PDFASMAPI	rPdfOpStart (RPDF_OPERATION *Ophandle)
	Start a new PDF operation.
RECERR PDFASMAPI	rPdfOpAddFile (RPDF_OPERATION ophandle, RPDF_DOC handle)
	Add a PDF document to the PDF operation.
RECERR PDFASMAPI	rPdfOpGetFirstFile (RPDF_OPERATION ophandle, RPDF_DOC handle, size_t numfiles, RPDF_FILEENUMERATOR *enumerator)
	Get the first assigned PDF document of a PDF operation.
RECERR PDFASMAPI	rPdfOpGetNextFile (RPDF_FILEENUMERATOR enumerator, RPDF_DOC *handle)
	Get the next assigned PDF document of a PDF operation.
RECERR PDFASMAPI	rPdfOpCloseFileEnumeration (RPDF_FILEENUMERATOR enumerator)
	Close the enumeration of the assigned PDF documents in the PDF operation.
RECERR PDFASMAPI	rPdfOpRotatePage (RPDF_OPERATION ophandle, RPDF_DOC handle, size_t position, RPDF_ROTATION rotation)
	Rotate a page in a PDF document as a part of a PDF operation.
RECERR PDFASMAPI	rPdfOpDeletePages (RPDF_OPERATION ophandle, RPDF_DOC handle, const size_t *PageIndexArr, size_t numpages)
	Delete one or more pages in a PDF document as a part of a PDF operation.
RECERR PDFASMAPI	rPdfOpCopyPages (RPDF_OPERATION ophandle, RPDF_DOC desthandle, size_t destposition, RPDF_DOC srchandle, const size_t *PageIndexArr, size_t numpages)
	Copy pages as a part of a PDF operation.
RECERR PDFASMAPI	rPdfOpMovePages (RPDF_OPERATION ophandle, RPDF_DOC handle, size_t destposition, const size_t *PageIndexArr, size_t numpages)
	Move pages as a part of a PDF operation.
RECERR PDFASMAPI	rPdfOpCancel (RPDF_OPERATION ophandle)
	Cancel a PDF operation.
RECERR PDFASMAPI	rPdfOpExecute (RPDF_OPERATION ophandle)
	Execute a PDF operation.
RECERR PDFASMAPI	rPdfOpInsertHPAGEs (RPDF_OPERATION ophandle, RPDF_DOC desthandle, size_t destposition, const HPAGE *srcpages, size_t srcpagecount, bool bImageOnly)
	Insert pages to the PDF given by HPAGE handles.
RECERR PDFASMAPI	rPdfOpMergeTextToPages (RPDF_OPERATION ophandle, RPDF_DOC desthandle, size_t destposition, const HPAGE *srcpages, size_t srcpagecount)
	Insert the text content of the given HPAGE handles to the specified PDF pages.
RECERR PDFASMAPI	rPdfGetPDFSecurityInfo (LPCTSTR pFileName, RPDF_ENCRYPTION encMethod, size_t keySize, RPDF_RESTRICTIONS secuRestrictions, bool hasMasterPassword, bool *hasUserPassword)
	Get PDF encryption information without opening it.
RECERR PDFASMCALL	rPdfOptOpen (LPCTSTR pFileName, LPCTSTR password, RPDF_DOC *handle)
	Open a PDF file.
RECERR PDFASMCALL	rPdfOptAddCommandStr (RPDF_DOC handle, LPCTSTR command)
	Add an optimization command string to a handle.
RECERR PDFASMCALL	rPdfOptimize (RPDF_DOC handle, LPCTSTR pOptFileName)
	Do the optimization process.

Detailed Description

This is the "C" level API of RecPDFAPI. RecPDF API-level of CSDK is supported on: Windows, Linux, Mac OS X.

This is the "C" level Page Oriented PDF File Manipulation API of OmniPage CSDK.

This part of RecAPI is an extension can be used both with KernelAPI and with RecAPIPlus. One of them should be initialized before initialization of RecPDF.

List of header files of this module:

recpdf.h - If RecPDF is used with KernelAPI, this file is enough to be included, because it includes KernelAPI.h. Using it with RecAPIPlus, RecApiPlus.h must be included as well.

The library file that should be linked is recpdf.lib, but there is an alternative solution: the dynamic linking using RecPDFS.

Enumeration Type Documentation

enum RPDF_ENCRYPTION

Encryption type of a PDF file.

Enumerator:

ENC_NO	Not encrypted.
ENC_RC4	RC4 algorithm.
ENC_AES	AES algorithm.

enum RPDF_RESTRICTIONS

PDF security restriction flags.

Enumerator:

PSR_NO_PRINT	Printing isn't allowed.
PSR_NO_HIPRINT	Print the document only low resolution mode.
PSR_NO_COPY	Can not copy the content to other document.
PSR_NO_EXTRACT_TEXT	Extracting the content is prohibited. (For accessibility usings for disabled users.)
PSR_NO_EXTRACT_PAGES	Extracting the pages is prohibited.
PSR_NO_CHANGE	Modifying the content is prohibited.
PSR_NO_ASSEMBLE	Document assemble is prohibited (can not insert, rotate, delete pages, and create bookmarks or thumbnails).
PSR_NO_ACROFORM	Filling in form fields are prohibited.
PSR_NO_ANNOT	Adding or modifying annotations are prohibited.

enum RPDF_ROTATION

Page rotation.

Enumerator:

PDFROT_NO	No rotation.
PDFROT_LEFT	Rotate counter clockwise.
PDFROT_RIGHT	Rotate clockwise.
PDFROT_HALFTURN	Rotate 180 degrees.

Function Documentation

RECERR PDFASMAPI rPdfClose ( RPDF_DOC handle )

Close a PDF document.

Destroys the PDF document object.

Return values:

RECERR

Parameters:

[in] handle Handle of the PDF document.

Note:: RecPDF API-level of CSDK is supported on: Windows, Linux, Mac OS X.; All unsaved data will be lost.; The handle won't be valid any more.

RECERR PDFASMAPI rPdfCompact	(	LPCTSTR	pInFileName,
		LPCTSTR	pOutFileName
	)

Compact a PDF document.

Save the compacted PDF document into a new file.

Return values:

RECERR

Parameters:

[in]	pInFileName	Full path of the input file.
[in]	pOutFileName	Full path of the output file.

Note:: RecPDF API-level of CSDK is supported on: Windows, Linux, Mac OS X.

RECERR PDFASMAPI rPdfFileHasText	(	RPDF_DOC	handle,
		size_t	position,
		bool *	bHasText
	)

Check if a page of the PDF document does have or doesn't have searchable text.

Return values:

RECERR

Parameters:

[in]	handle	Handle of the PDF document.
[in]	position	Page index in the PDF document.
[out]	bHasText	Existence of searchable text in the page of the PDF document.

Note:: RecPDF API-level of CSDK is supported on: Windows, Linux, Mac OS X.

RECERR PDFASMAPI rPdfGetOp	(	RPDF_DOC	handle,
		RPDF_OPERATION *	ophandle
	)

Get the PDF operation assigned to a PDF document.

At a time only one PDF operation can be assigned to a PDF document. If there is such an PDF operation, this function will give it back. If there is no such PDF operation NULL will be returned.

Return values:

RECERR

Parameters:

[in]	handle	Handle of the PDF document.
[out]	ophandle	The return value is the handle of the PDF operation if an PDF operation is assigned to the PDF document, otherwise NULL.

Note:: RecPDF API-level of CSDK is supported on: Windows, Linux, Mac OS X.

RECERR PDFASMAPI rPdfGetPageCount	(	RPDF_DOC	handle,
		size_t *	pnPages
	)

Get the page count of a PDF document.

Return values:

RECERR

Parameters:

[in]	handle	Handle of the PDF document.
[out]	pnPages	Count of pages in the PDF document.

Note:: RecPDF API-level of CSDK is supported on: Windows, Linux, Mac OS X.

RECERR PDFASMAPI rPdfGetPath	(	RPDF_DOC	handle,
		LPTSTR	buffer,
		size_t	buflen
	)

Get the path of the PDF document.

Read the path string from the PDF file.

Return values:

RECERR

Parameters:

[in]	handle	Handle of the PDF document.
[out]	buffer	String buffer to store the full path of the PDF document.
[out]	buflen	Length of the buffer.

Note:: RecPDF API-level of CSDK is supported on: Windows, Linux, Mac OS X.

RECERR PDFASMAPI rPdfGetPDFSecurityInfo	(	LPCTSTR	pFileName,
		RPDF_ENCRYPTION *	encMethod,
		size_t *	keySize,
		RPDF_RESTRICTIONS *	secuRestrictions,
		bool *	hasMasterPassword,
		bool *	hasUserPassword
	)

Get PDF encryption information without opening it.

Return values:

RECERR

Parameters:

[in]	pFileName	Full path of the source file.
[out]	encMethod	Encryption method of the PDF file. (Can be NULL if not needed.)
[out]	keySize	Encryption's key size. (Can be NULL if not needed.)
[out]	secuRestrictions	Restrictions on the PDF file. (Can be NULL if not needed.)
[out]	hasMasterPassword	Whether the PDF file has master password. (Can be NULL if not needed.)
[out]	hasUserPassword	Whether the PDF file has user password. (Can be NULL if not needed.)

Note:: RecPDF API-level of CSDK is supported on: Windows, Linux, Mac OS X.

RECERR PDFASMAPI rPdfInit ( void )

Initialize the RecPDF.

The rPdfInit starts the PDF assembler SDK. All RecPDF functions must be called between an rPdfInit and an rPdfQuit calls.

Return values:

RECERR

Note:: RecPDF API-level of CSDK is supported on: Windows, Linux, Mac OS X.; Before rPdfInit a kRecInit or RecInitPlus must be called to initialize the CSDK.

RECERR PDFASMAPI rPdfOpAddFile	(	RPDF_OPERATION	ophandle,
		RPDF_DOC	handle
	)

Add a PDF document to the PDF operation.

A PDF operation is able to use only those PDF document whose are assigned to it.

Return values:

RECERR

Parameters:

[in]	ophandle	Handle of the PDF operation.
[in]	handle	Handle of the PDF document.

Note:: RecPDF API-level of CSDK is supported on: Windows, Linux, Mac OS X.; Once a PDF document is assigned to a PDF operation, there is no way to unassign it.

RECERR PDFASMAPI rPdfOpCancel ( RPDF_OPERATION ophandle )

Cancel a PDF operation.

Destroys a PDF operation without executing it. This PDF operation handle cannot be used anymore. All page objects will be freed up and cannot be used anymore. All PDF documents will show the same state as before the PDF operation has started.

Return values:

RECERR

Parameters:

[in] ophandle Handle of the PDF operation.

Note:: RecPDF API-level of CSDK is supported on: Windows, Linux, Mac OS X.

RECERR PDFASMAPI rPdfOpCloseFileEnumeration ( RPDF_FILEENUMERATOR enumerator )

Close the enumeration of the assigned PDF documents in the PDF operation.

Destroys the enumerator of the assigned PDF documents.

Return values:

RECERR

Parameters:

[in] enumerator Handle of the PDF document enumerator.

Note:: RecPDF API-level of CSDK is supported on: Windows, Linux, Mac OS X.

RECERR PDFASMAPI rPdfOpCopyPages	(	RPDF_OPERATION	ophandle,
		RPDF_DOC	desthandle,
		size_t	destposition,
		RPDF_DOC	srchandle,
		const size_t *	PageIndexArr,
		size_t	numpages
	)

Copy pages as a part of a PDF operation.

Add a copy page command to a PDF operation. It can copy pages from a PDF document to another PDF document or inside a single PDF document.

Return values:

RECERR

Parameters:

[in]	ophandle	Handle of the PDF operation.
[in]	desthandle	Handle of the destination PDF document.
[in]	destposition	Starting page index in the destination PDF document. The first copied page will get this page index. All other copied pages will be copied continually after the first one. If this equals to the count of pages of the destination PDF document or (size_t)-1, then the new pages will be appended to the PDF document.
[in]	srchandle	Handle of the source PDF document. It can be the same as the desthandle. If it is NULL, then the source document will be the same as the destination.
[in]	PageIndexArr	Array of page indices in the source PDF document.
[in]	numpages	Count of pages to copy. This is the number of elements in the PageIndexArr array.

Note:: RecPDF API-level of CSDK is supported on: Windows, Linux, Mac OS X.; The command takes place when the PDF operation is executed.; After the call all functions will see as if the copy has been already taken place.

RECERR PDFASMAPI rPdfOpDeletePages	(	RPDF_OPERATION	ophandle,
		RPDF_DOC	handle,
		const size_t *	PageIndexArr,
		size_t	numpages
	)

Delete one or more pages in a PDF document as a part of a PDF operation.

Add a page delete command to a PDF operation.

Return values:

RECERR

Parameters:

[in]	ophandle	Handle of the PDF operation.
[in]	handle	Handle of the PDF document.
[in]	PageIndexArr	Array of the page indices in the PDF document.
[in]	numpages	Count of pages to delete. This is the number of elements in the PageIndexArr.

Note:: RecPDF API-level of CSDK is supported on: Windows, Linux, Mac OS X.; The command takes place when the PDF operation is executed.; After the call all functions will see as if the deletion has been already taken place.

RECERR PDFASMAPI rPdfOpen	(	LPCTSTR	pFileName,
		LPCTSTR	password,
		RPDF_DOC *	handle
	)

Open a PDF file.

Create a PDF document object, and assign an existing PDF file to it. Then gives back a handle for the PDF document.

Return values:

RECERR

Parameters:

[in]	pFileName	Full path of the source file.
[in]	password	Pointer to the PDF password or NULL or empty string if no password is needed.
[out]	handle	PDF document handle.

Note:: RecPDF API-level of CSDK is supported on: Windows, Linux, Mac OS X.

RECERR PDFASMAPI rPdfOpExecute ( RPDF_OPERATION ophandle )

Execute a PDF operation.

Execute a PDF operation and after the execution destroy it. This PDF operation handle cannot be used anymore. All page objects will be freed up and cannot be used anymore.

Return values:

RECERR

Parameters:

[in] ophandle Handle of the PDF operation.

Note:: RecPDF API-level of CSDK is supported on: Windows, Linux, Mac OS X.; There is no guarantee that all commands will be executed.

RECERR PDFASMAPI rPdfOpGetFirstFile	(	RPDF_OPERATION	ophandle,
		RPDF_DOC *	handle,
		size_t *	numfiles,
		RPDF_FILEENUMERATOR *	enumerator
	)

Get the first assigned PDF document of a PDF operation.

Start the enumeration of the assigned PDF document of a PDF operation. The created file enumerator must be freed up after use with the rPdfOpCloseFileEnumeration function call.

Return values:

RECERR

Parameters:

[in]	ophandle	Handle of the PDF operation.
[out]	handle	Handle of the first PDF document.
[out]	numfiles	Count of assigned PDF documents in the PDF operation.
[out]	enumerator	New enumerator handle. This handle can be used to continue the enumeration with the rPdfOpGetNextFile.

Note:: RecPDF API-level of CSDK is supported on: Windows, Linux, Mac OS X.; By the time when the enumeration takes place the PDF operation object or the referenced PDF documents may be destroyed. If the PDF operation object is destroyed a referenced PDF document may be attached to another PDF operation.

RECERR PDFASMAPI rPdfOpGetNextFile	(	RPDF_FILEENUMERATOR	enumerator,
		RPDF_DOC *	handle
	)

Get the next assigned PDF document of a PDF operation.

Step the enumerator of the assigned PDF document and give back the next one.

Return values:

RECERR

Parameters:

[in]	enumerator	Handle of the PDF document enumerator.
[out]	handle	Assigned PDF document in the PDF operation.

Note:: RecPDF API-level of CSDK is supported on: Windows, Linux, Mac OS X.

RECERR PDFASMAPI rPdfOpInsertHPAGEs	(	RPDF_OPERATION	ophandle,
		RPDF_DOC	desthandle,
		size_t	destposition,
		const HPAGE *	srcpages,
		size_t	srcpagecount,
		bool	bImageOnly
	)

Insert pages to the PDF given by HPAGE handles.

Add an insert HPAGE command to a PDF operation. It can insert pages to a PDF document by HPAGE.

Return values:

RECERR

Parameters:

[in]	ophandle	Handle of the PDF operation.
[in]	desthandle	Handle of the destination PDF document.
[in]	destposition	Starting page index in the destination PDF document. The first inserted page will get this page index. All other inserted pages will be inserted continually after the first one. If this equals to the count of pages of the destination PDF document or (size_t)-1, then the new pages will be appended to the PDF document.
[in]	srcpages	Array of pages given by HPAGEs.
[in]	srcpagecount	Count of HPAGEs to insert. This is the number of elements in the srcpages array.
[in]	bImageOnly	If this parameter is `true`, the command inserts only the images without the recognized text.

Note:: RecPDF API-level of CSDK is supported on: Windows, Linux, Mac OS X.; The command takes place when the PDF operation is executed.; The HPAGEs can free after the end of the operation.; After the call all functions will see as if the insertion has been already taken place.

RECERR PDFASMAPI rPdfOpMergeTextToPages	(	RPDF_OPERATION	ophandle,
		RPDF_DOC	desthandle,
		size_t	destposition,
		const HPAGE *	srcpages,
		size_t	srcpagecount
	)

Insert the text content of the given HPAGE handles to the specified PDF pages.

Add a Make Pages Searchable command to a PDF operation. It can merge the text content of a HPAGE to the specified pages.

Return values:

RECERR

Parameters:

[in]	ophandle	Handle of the PDF operation.
[in]	desthandle	Handle of the destination PDF document.
[in]	destposition	Starting page index in the destination PDF document. The first searchable page will get this page index. All other searchable pages will continually after the first one.
[in]	srcpages	Array of pages given by HPAGEs.
[in]	srcpagecount	Count of HPAGEs to insert. This is the number of elements in the srcpages array.

Note:: RecPDF API-level of CSDK is supported on: Windows, Linux, Mac OS X.; The command takes place when the PDF operation is executed.; After this function call, the HPAGE can free by the caller.; After the call all functions will see as if the insertion has been already taken place.

RECERR PDFASMAPI rPdfOpMovePages	(	RPDF_OPERATION	ophandle,
		RPDF_DOC	handle,
		size_t	destposition,
		const size_t *	PageIndexArr,
		size_t	numpages
	)

Move pages as a part of a PDF operation.

Add a move page command to a PDF operation. It can move pages inside a single PDF document.

Return values:

RECERR

Parameters:

[in]	ophandle	Handle of the PDF operation.
[in]	handle	Handle of the PDF document.
[in]	destposition	The starting page index. This will be the page index of the first moved page. All other move pages will be moved continually after the first one. If this equals to the count of pages of the destination PDF document or (size_t)-1, then the new pages will be appended to the PDF document.
[in]	PageIndexArr	Array of page indices in the source PDF document.
[in]	numpages	Count of pages to copy. This is the number of elements in the PageIndexArr array.

Note:: RecPDF API-level of CSDK is supported on: Windows, Linux, Mac OS X.; The command takes place when the PDF operation is executed.; After the call all functions will see as if the move has been already taken place.

RECERR PDFASMAPI rPdfOpRotatePage	(	RPDF_OPERATION	ophandle,
		RPDF_DOC	handle,
		size_t	position,
		RPDF_ROTATION	rotation
	)

Rotate a page in a PDF document as a part of a PDF operation.

Add a page rotate command to a PDF operation.

Return values:

RECERR

Parameters:

[in]	ophandle	Handle of the PDF operation.
[in]	handle	Handle of the PDF document.
[in]	position	Page index in the PDF document.
[in]	rotation	How much rotate the page.

Note:: RecPDF API-level of CSDK is supported on: Windows, Linux, Mac OS X.; The command takes place when the PDF operation is executed.; After the call all functions will see as if the rotation has been already taken place.; If the page is a part of a page object, then it will be removed from the page object.

RECERR PDFASMAPI rPdfOpStart ( RPDF_OPERATION * Ophandle )

Start a new PDF operation.

Create a new PDF operation object.

Return values:

RECERR

Parameters:

[out] Ophandle Handle of the new PDF operation.

Note:: RecPDF API-level of CSDK is supported on: Windows, Linux, Mac OS X.

RECERR PDFASMCALL rPdfOptAddCommandStr	(	RPDF_DOC	handle,
		LPCTSTR	command
	)

Add an optimization command string to a handle.

See the possible command strings in the RecPDF help! You can specify more command strings by calling this function more than once

Return values:

RECERR

Parameters:

[in]	handle	Handle of the PDF operation.
[in]	command	Commands, see the command descriptions.

Note:: RecPDF API-level of CSDK is supported on: Windows, Linux, Mac OS X.

RECERR PDFASMCALL rPdfOptimize	(	RPDF_DOC	handle,
		LPCTSTR	pOptFileName
	)

Do the optimization process.

Return values:

RECERR

Parameters:

[in]	handle	Handle of the PDF operation.
[in]	pOptFileName	Full path of the optimized output file.

Note:: RecPDF API-level of CSDK is supported on: Windows, Linux, Mac OS X.

RECERR PDFASMCALL rPdfOptOpen	(	LPCTSTR	pFileName,
		LPCTSTR	password,
		RPDF_DOC *	handle
	)

Open a PDF file.

Create a PDF document object, and assign an existing PDF file to it. Then gives back a handle for the PDF document. This handle can be used only for PDF optimalization. Do not add to an Operation

Return values:

RECERR

Parameters:

[in]	pFileName	Full path of the source file.
[in]	password	Pointer to the PDF password or NULL or empty string if no password is needed.
[out]	handle	PDF document handle.

Note:: RecPDF API-level of CSDK is supported on: Windows, Linux, Mac OS X.

RECERR PDFASMAPI rPdfQuit ( void )

Uninitialize the RecPDF.

The rPdfQuit stops the PDF assembler SDK. All RecPDF functions must be called between an rPdfInit and an rPdfQuit calls.

Return values:

RECERR

Note:: RecPDF API-level of CSDK is supported on: Windows, Linux, Mac OS X.; After rPdfQuit a kRecQuit or RecQuitPlus must be called to shut down the CSDK.

Typedefs

Enumerations

Functions

Detailed Description

Enumeration Type Documentation

Function Documentation