From:	"Ben Alford" <benjamin DOT alford AT surrey DOT uni DOT ntl DOT com>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Reading in Data
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Date:	Sat, 22 Apr 2000 00:05:24 +0100
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To:	djgpp AT delorie DOT com
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Hi

I am trying to read data from a file. The file is in binary format. The data
is either 1,2 or 4 bytes.
I need to convert the byte information into an integer value.
The technique that I have tried for reading a field of 2 bytes would be,

char twobyte[3]

 fread(twobytes, sizeof(twobytes), 1, FILE)
strcpy(twobytes, twobytes, 2)
 twobyte[2] = '\0'
 num = (int)(unsigned char)twobyte[1]*256 + (int)(unsigned char)twobyte[0]

This sort of works but feels nasty. It doesn't work for values that are
negative.

Any ideas would be very appreciated

thanks

Ben

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