Using grep to match md5 hashes

Question

How can I match md5 hashes with the grep command?

In php I used this regular expression pattern in the past:

/^[0-9a-f]{32}$/i

But I t

Answer 1

A little one-liner which works cross platform on Linux and OSX, only returning the MD5 hash value (replace YOURFILE with your filename):

[ "$(uname)" = "Darwin" ] && { MD5CMD=md5; } || { MD5CMD=md5sum; } \
    && { ${MD5CMD} YOURFILE | grep -o "[a-fA-F0-9]\{32\}"; }

Example:

$ touch YOURFILE
$ [ "$(uname)" = "Darwin" ] && { MD5CMD=md5; } || { MD5CMD=md5sum; } && { ${MD5CMD} YOURFILE | grep -o "[a-fA-F0-9]\{32\}"; }
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