You may wish to note that your question and your regex appear to rely on passwordfile actually containing passwords in a human readable format.

Some do.

But that's an exceedingly insecure (read: almost useless) way to keep a password file. Anyone who can access it can read the passwords. Mere encoding or even encrypting isn't much better.

OTH, if the system being protected by the p/w file hashes the p/w (with an unreverseable -- well "unreversable"-so-far-as-we-know-right-now -- algorithm and stores the value of the hash rather than the p/w itself in the p/w file, future ID checks can be performed by hashing the p/w entered at the challenge (login) screen and seeing if it matches the hash in the p/w file. Of course, that doesn't begin to solve all the possible problems (interception between keystroke and transmission, interception en route, etc., etc., etc....).

As to the insufficient info in your question and questionable regex technique, see the replies above.

In reply to passwords in Re: How Do I Read Data From A File? by ww
in thread How Do I Read Data From A File? by rboggala

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