=head2 Extensions
+Perl ships with a number of standard extensions. These are contained
+in the ext/ subdirectory.
+
By default, Configure will offer to build every extension which appears
to be supported. For example, Configure will offer to build GDBM_File
only if it is able to find the gdbm library. (See examples below.)
-B, DynaLoader, Fcntl, IO, and attrs are always built by default.
Configure does not contain code to test for POSIX compliance, so POSIX
is always built by default as well. If you wish to skip POSIX, you can
set the Configure variable useposix=false either in a hint file or from
-the Configure command line. Similarly, the Opcode extension is always
-built by default, but you can skip it by setting the Configure variable
-useopcode=false either in a hint file for from the command line.
+the Configure command line.
If you unpack any additional extensions in the ext/ directory before
running Configure, then Configure will offer to build those additional
version. (Configure will suggest this as the default.)
In summary, here are the Configure command-line variables you can set
-to turn off each extension:
+to turn off various extensions. All others are included by default.
- B (Always included by default)
DB_File i_db
DynaLoader (Must always be included as a static extension)
- Fcntl (Always included by default)
GDBM_File i_gdbm
- IO (Always included by default)
NDBM_File i_ndbm
ODBM_File i_dbm
POSIX useposix
- SDBM_File (Always included by default)
Opcode useopcode
Socket d_socket
Threads use5005threads
- attrs (Always included by default)
Thus to skip the NDBM_File extension, you can use
for the default answer, but it will also point out the discrepancy to
you.
-Finally, if you have dynamic loading (most modern Unix systems do)
+Finally, if you have dynamic loading (most modern systems do)
remember that these extensions do not increase the size of your perl
executable, nor do they impact start-up time, so you probably might as
well build all the ones that will work on your system.
If you are distributing a modified version of perl (perhaps as part of
a larger package) please B<do> modify these installation instructions
and the contact information to match your distribution.
-