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How to read a binary file LabWindow

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I opened a file and specify the file format as binary using VAL_BINARY. Somehow I can not find a function that can be used to read.

           OpenFile( inputFile, VAL_READ_ONLY, VAL_OPEN_AS_IS , VAL_BINARY );

 

I tried to use read, it complaints C99 does not support this.

 

Well, all I want to do is read in a binary file byte by byte.

 

Thank you.

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Accepted by topic author qing22

ReadFile () is the function you need to use: you can pass a unsigned char variable to retrieve the file content and either read the file one byte at a time (highly inefficient) or read it in blocks and scan the output buffer to decode it (better).

 

These are general rules, there may be different ways to read a binary file, e.g. using a struct variable to automatically decode the file if you already know its structure.



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Use the standard ANSI C file input/output functions fopen, fread, and fclose.

 

http://www.cplusplus.com/reference/cstdio/fopen/

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Thank you. ReadFile works for me:

- the LabWindows complaints warning of using unsigned char* , instead of char*

- It seems like have to read byte by byte, instead of read a block.

 

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@qing22  ha scritto:

- It seems like have to read byte by byte, instead of read a block.

 

You're right about the type of the variable, sorry for that.

ReadFile (fileHandle, buffer, nBytes); should permit you to read nBytes out from the file.



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