Parameters

dwTimeout

Time in milliseconds that the engine scans until finding a decode. The timeout value must be greater than zero.

pchMessage

Upon successful return, this variable points to the decoded message. The caller should allocate enough memory for this buffer to hold the largest possible decode message. See oemGetMaxMessageChars (page 2-12).

pchCodeID

Upon successful return, this variable points to the Hand Held Products Code ID for the decoded symbology. See Symbology Identifiers (page 3-1).

pchAIMID

Upon successful return, this variable points to the AIM ID for the decoded symbology. See Symbology Identifiers (page 3-1).

pchSymModifier

Upon successful return, this variable points to the code modifier for the decoded symbology. See Symbology Identifiers (page 3-1).

pnLength

Upon successful return, this variable points to the length of the bar code data that was captured. The length is represented in terms of the number of TCHAR characters in the TCHAR *pchMessage.

fpCallBack

Pass in this pointer to a parameterless BOOL-returning function to allow for an external event that causes a return from oemWaitForDecode. As long as the function pointed to by fpCallBack returns TRUE, oemWaitForDecode continues to attempt to decode a symbol. If the function pointed to by fpCallBack returns FALSE, then oemWaitForDecode returns with a Result_t of RESULT_ERR_NOTRIGGER. OemWaitForDecode also returns if it gets a valid decode or the dwTimeout occurs. Setting the parameter to NULL prevents the API from calling this callback function. In that case, oemWaitForDecode only returns after a valid decode of dwTimeout has passed without a successful decode.

oemWaitForDecodeRaw

This function causes the engine to start scanning for a decodable symbol. This function does not return until either a symbol is decoded, or the timeout period has elapsed. If a message was decoded, it is returned in this function's parameters in raw form as byte values.

Result_t oemWaitForDecodeRaw (

DWORD dwTimeout, BYTE *pchMessage, BYTE *pchCodeID, BYTE *pchAIMID, BYTE *pchSymModifier, WORD *pnLength, BOOL (*fpCallBack) (void)

)

Return Values

RESULT_SUCCESS

RESULT_ERR_ENGINEBUSY

RESULT_ERR_PARAMETER

RESULT_ERR_NOTRIGGER

RESULT_ERR_NODECODE

RESULT_ERR_NOIMAGE

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IMAGETEAM™ 4X00 Series Software Development Kit (SDK) User’s Guide

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Hand Held Products 4X00 manual OemWaitForDecodeRaw, Resultt oemWaitForDecodeRaw