It could give a false positive if every byte of a 'binary' file happened to contain the code of an ASCII character. (Can you tolerate an extremely rare error?)

I know only one binary file that intentionally contains only ASCII characters: The EICAR test file. Here it is, in its full glory:

X5O!P%@AP[4\PZX54(P^)7CC)7}$EICAR-STANDARD-ANTIVIRUS-TEST-FILE!$H+H*

[download]

It is a DOS executable that just prints the embedded text "EICAR-STANDARD-ANTIVIRUS-TEST-FILE!" and then exits.

Alexander

--
Today I will gladly share my knowledge and experience, for there are no sweeter words than "I told you so". ;-)

In reply to Re^2: Question regarding a regex by afoken
in thread Question regarding a regex by CrashBlossom

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