I know I'm probably the last person on earth using dbmopen() to tie hashes, but here's a question -- if I do this: 
    dbmopen(%my_hash,'my_data',0777) || die "$!";

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and the file has not yet been created, it will automagically be created. The only error I'm likely to get is if I don't have permission to create files in that directory or something.

Is there a way to find out if a database file already exists before I open it and start (possibly) clobbering its values?

I know on the particular system I'm using right now, that implies the creation of a file called 'my_data.db', but on another system, it implies the creation of two files, 'my_data.pag' and 'my_data.dir' -- because it uses NDBM, or something.

In my case, I know the system so I can just do an "if file exists 'my_data.db'", but if I can't be sure what the filename is every time, can I in some other way logically test whether there's already a database file before I do this: 

    dbmopen(%my_hash,'my_data',0777) || die "$!";
    $my_hash{'something_really_important'} = '';

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?
--

“Every bit of code is either naturally related to the problem at hand, or else it's an accidental side effect of the fact that you happened to solve the problem using a digital computer.”
M-J D

In reply to dbmopen() test if file exists already? by Cody Pendant

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