Another way to compare the contents of two files at the byte level is to hash both of them and compare the hashes. (it's the entire purpose of digest hashes).

$ dd if=/dev/urandom of=file1 bs=1K count=10
10+0 records in
10+0 records out
10240 bytes (10 kB, 10 KiB) copied, 0.000148608 s, 68.9 MB/s
$ dd if=/dev/urandom of=file2 bs=1K count=10
10+0 records in
10+0 records out
10240 bytes (10 kB, 10 KiB) copied, 0.000145675 s, 70.3 MB/s
$ ls -l
total 24
-rw-r--r-- 1 foo foo 10240 Feb  9 17:47 file1
-rw-r--r-- 1 foo foo 10240 Feb  9 17:47 file2
$ sha256sum *
7986a677d3ef9a4f71ba18a5a7bd3a5f9a0c2d16939b4a43cd49fde86cef5a2f  file
+1
3c946e3212d808dbb7471eecc07e454c459352a6a3e25230288fe5faf08af555  file
+2
[download]

This shows that despite file1 and file2 having precisely the same size, their contents differ because the SHA256 hashes differ. See sha256sum for more.

---

---

Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!

Titles consisting of a single word are discouraged, and in most cases are disallowed outright.

Read Where should I post X? if you're not absolutely sure you're posting in the right place.

Please read these before you post! —

• How do I compose an effective node title?
• How do I post a question effectively?
• Markup in the Monastery

Posts may use any of the Perl Monks Approved HTML tags:

a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr

You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)

	For:		Use:
	&		&
	<		&lt;
	>		&gt;
	[		&#91;
	]		&#93;

Link using PerlMonks shortcuts! What shortcuts can I use for linking?

See Writeup Formatting Tips and other pages linked from there for more info.