Converting ascii hex values to hex bytes

Mark Pledger mpledger at cti1.UUCP
Wed Oct 17 21:08:26 AEST 1990


I have a little stumper of a question.  I am writing software that accesses
a configuration file that stores IP addresses.  The IP addresses are stored
as raw hex bytes.  For example, an IP address of say 122.10.10.44 is stored
in the configuration file as 4 bytes 7A-0A-0A-2C.  Now I am using fread()
and fwrite() to get a lot of different configuration data.  What I want to 
do is to be able to convert 122.10.10.44 into a character string of 4 bytes
that equals "\x7a\x0a\x0a\x2c".  How can I convert the ascii representation
into hex?  I tried using itoa(), but the result is in ascii character format
so if you used itoa(44,result,16), result[] = "2C".  When written to disk,
the result[] string is actually written to disk as an ascii 2 (32h) and an
ascii C (43h).  What I want is one byte equalling "\x2c".

Can anybody give me a hand?  Thanks in advance.









-- 
Sincerely,


Mark Pledger

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