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Checking md5sum for a file

I have two files hello.txt

andhello.txt.md5

MD5 output is in lower format

cat hello.txt.md5 
b1946ac92492d2347c6235b4d2611184

I wrote a simple script to check md5sum.

csum=$(cat hello.txt.md5)
echo "$csum hello.txt" | md5sum -c

This script works fine with Ubuntu 13.10

but it throws below error in Ubuntu 12.04

.

md5sum: standard input: no properly formatted MD5 checksum strings found

Can anyone show me how to do this in Ubuntu12.04.

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2 answers


At least my md5sum files have two spaces between the checksum and the filename. Tested your script and it didn't work, added space between $ csum and hello.txt and it did.



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This may be due to some change between versions md5sum

.

Running md5sum <file1> <file2>

on both versions should give you an example of what format each version expects.

Specifically, the md5sum

man page says:



The default mode is to print a line with a checksum, character type ('*' for binary, '' for text) and a name for each file.

So, to check for text mode, two spaces usually have to be present (indeed, checking with help md5sum -t t.txt

confirms this). I guess the new version has raised this requirement.

Indeed, here's a GNU coreutils link called "md5sum: Handle BSD Reverse Format Checksums" from 2011-09-16. It makes md5sum

guessing between the two formats.
End was released incoreutils 8.14

, whereas Ubuntu 12.04 is using8.13

.

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