diff options
Diffstat (limited to 'ext')
| -rw-r--r-- | ext/NDBM_File/NDBM_File.pm | 90 | ||||
| -rw-r--r-- | ext/ODBM_File/ODBM_File.pm | 87 | ||||
| -rw-r--r-- | ext/SDBM_File/SDBM_File.pm | 2 |
3 files changed, 167 insertions, 12 deletions
diff --git a/ext/NDBM_File/NDBM_File.pm b/ext/NDBM_File/NDBM_File.pm index f98669f486..c9ef6993a8 100644 --- a/ext/NDBM_File/NDBM_File.pm +++ b/ext/NDBM_File/NDBM_File.pm @@ -24,15 +24,93 @@ NDBM_File - Tied access to ndbm files =head1 SYNOPSIS - use NDBM_File; - use Fcntl; # for O_ constants + use Fcntl; # For O_RDWR, O_CREAT, etc. + use NDBM_File; - tie(%h, 'NDBM_File', 'Op.dbmx', O_RDWR|O_CREAT, 0640); + # Now read and change the hash + $h{newkey} = newvalue; + print $h{oldkey}; + ... + + untie %h; + +=head1 DESCRIPTION + +C<NDBM_File> establishes a connection between a Perl hash variable and +a file in NDBM_File format;. You can manipulate the data in the file +just as if it were in a Perl hash, but when your program exits, the +data will remain in the file, to be used the next time your program +runs. - untie %h; +Use C<NDBM_File> with the Perl built-in C<tie> function to establish +the connection between the variable and the file. The arguments to +C<tie> should be: -=head1 DESCRIPTION +=over 4 + +=item 1. + +The hash variable you want to tie. + +=item 2. + +The string C<"NDBM_File">. (Ths tells Perl to use the C<NDBM_File> +package to perform the functions of the hash.) + +=item 3. + +The name of the file you want to tie to the hash. + +=item 4. + +Flags. Use one of: + +=over 2 + +=item C<O_RDONLY> + +Read-only access to the data in the file. + +=item C<O_WRONLY> + +Write-only access to the data in the file. + +=item C<O_RDWR> + +Both read and write access. + +=back + +If you want to create the file if it does not exist, add C<O_CREAT> to +any of these, as in the example. If you omit C<O_CREAT> and the file +does not already exist, the C<tie> call will fail. + +=item 5. + +The default permissions to use if a new file is created. The actual +permissions will be modified by the user's umask, so you should +probably use 0666 here. (See L<perlfunc/umask>.) + +=back + +=head1 DIAGNOSTICS + +On failure, the C<tie> call returns an undefined value and probably +sets C<$!> to contain the reason the file could not be tied. + +=head2 C<ndbm store returned -1, errno 22, key "..." at ...> + +This warning is emmitted when you try to store a key or a value that +is too long. It means that the change was not recorded in the +database. See BUGS AND WARNINGS below. + +=head1 BUGS AND WARNINGS + +There are a number of limits on the size of the data that you can +store in the NDBM file. The most important is that the length of a +key, plus the length of its associated value, may not exceed 1008 +bytes. -See L<perlfunc/tie>, L<perldbmfilter> +See L<perlfunc/tie>, L<perldbmfilter>, L<Fcntl> =cut diff --git a/ext/ODBM_File/ODBM_File.pm b/ext/ODBM_File/ODBM_File.pm index 57fe4c352d..732ed60930 100644 --- a/ext/ODBM_File/ODBM_File.pm +++ b/ext/ODBM_File/ODBM_File.pm @@ -20,14 +20,93 @@ ODBM_File - Tied access to odbm files =head1 SYNOPSIS + use Fcntl; # For O_RDWR, O_CREAT, etc. use ODBM_File; - tie(%h, 'ODBM_File', 'Op.dbmx', O_RDWR|O_CREAT, 0640); + # Now read and change the hash + $h{newkey} = newvalue; + print $h{oldkey}; + ... + + untie %h; + +=head1 DESCRIPTION + +C<ODBM_File> establishes a connection between a Perl hash variable and +a file in ODBM_File format;. You can manipulate the data in the file +just as if it were in a Perl hash, but when your program exits, the +data will remain in the file, to be used the next time your program +runs. - untie %h; +Use C<ODBM_File> with the Perl built-in C<tie> function to establish +the connection between the variable and the file. The arguments to +C<tie> should be: -=head1 DESCRIPTION +=over 4 + +=item 1. + +The hash variable you want to tie. + +=item 2. + +The string C<"ODBM_File">. (Ths tells Perl to use the C<ODBM_File> +package to perform the functions of the hash.) + +=item 3. + +The name of the file you want to tie to the hash. + +=item 4. + +Flags. Use one of: + +=over 2 + +=item C<O_RDONLY> + +Read-only access to the data in the file. + +=item C<O_WRONLY> + +Write-only access to the data in the file. + +=item C<O_RDWR> + +Both read and write access. + +=back + +If you want to create the file if it does not exist, add C<O_CREAT> to +any of these, as in the example. If you omit C<O_CREAT> and the file +does not already exist, the C<tie> call will fail. + +=item 5. + +The default permissions to use if a new file is created. The actual +permissions will be modified by the user's umask, so you should +probably use 0666 here. (See L<perlfunc/umask>.) + +=back + +=head1 DIAGNOSTICS + +On failure, the C<tie> call returns an undefined value and probably +sets C<$!> to contain the reason the file could not be tied. + +=head2 C<odbm store returned -1, errno 22, key "..." at ...> + +This warning is emmitted when you try to store a key or a value that +is too long. It means that the change was not recorded in the +database. See BUGS AND WARNINGS below. + +=head1 BUGS AND WARNINGS + +There are a number of limits on the size of the data that you can +store in the ODBM file. The most important is that the length of a +key, plus the length of its associated value, may not exceed 1008 +bytes. -See L<perlfunc/tie>, L<perldbmfilter> +See L<perlfunc/tie>, L<perldbmfilter>, L<Fcntl> =cut diff --git a/ext/SDBM_File/SDBM_File.pm b/ext/SDBM_File/SDBM_File.pm index 438b8d02c1..b3502b9837 100644 --- a/ext/SDBM_File/SDBM_File.pm +++ b/ext/SDBM_File/SDBM_File.pm @@ -103,8 +103,6 @@ This warning is emmitted when you try to store a key or a value that is too long. It means that the change was not recorded in the database. See BUGS AND WARNINGS below. - - =head1 BUGS AND WARNINGS There are a number of limits on the size of the data that you can |