Subject: Bug in cmp(1)
To: None <netbsd-bugs@sun-lamp.cs.berkeley.edu>
From: Bob Kemp <rsk@ecs.soton.ac.uk>
List: netbsd-bugs
Date: 03/25/1994 11:37:47
Sorry, I don't have send-pr here nor a NetBSD m/c on the internet, so...
Description:
"cat file1 | cmp - file2" only works for small files but
"cmp - file1 < file2" works fine.
The former gives the message that the files differ at character 4097,
even if file1 == file2 !
It looks like a problem with reads on a pipe -- cmp doesn't realise
it must do ultiple reads to fill its buffer.
Repeat-By:
Create a file, In say, of about 10k (say). More than 4k anyhow.
cmp In In # works fine
cat In | cmp - In # produces an error message
cmp - In < In # works fine
Bob
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