DBMOPEN

dbmopen ASSOC,DBNAME,MODE

[This function has been superseded by the tie() function.]

This binds a dbm(3) or ndbm(3) file to an associative array. ASSOC is the name of the associative array. (Unlike normal open, the first argument is NOT a filehandle, even though it looks like one). DBNAME is the name of the database (without the .dir or .pag extension). If the database does not exist, it is created with protection specified by MODE (as modified by the umask() ). If your system only supports the older DBM functions, you may perform only one dbmopen() in your program. If your system has neither DBM nor ndbm, calling dbmopen() produces a fatal error.

If you don't have write access to the DBM file, you can only read associative array variables, not set them. If you want to test whether you can write, either use file tests or try setting a dummy array entry inside an eval() , which will trap the error.

Note that functions such as keys() and values() may return huge array values when used on large DBM files. You may prefer to use the each() function to iterate over large DBM files. Example:

# print out history file offsets dbmopen(%HIST,'/usr/lib/news/history',0666); while (($key,$val) = each %HIST) { print $key, ' = ', unpack('L',$val), "\n"; } dbmclose(%HIST);

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