=back
+=head2 Portability
+
+Perl was born in UNIX and therefore it can access all the common UNIX
+system calls. In non-UNIX environments the functionality of many
+UNIX system calls may not be available or the details of the available
+functionality may be slightly different. The Perl functions affected
+by this are:
+
+C<-X>, C<binmode>, C<chmod>, C<chown>, C<chroot>, C<crypt>,
+C<dbmclose>, C<dbmopen>, C<dump>, C<endgrent>, C<endhostent>,
+C<endnetent>, C<endprotoent>, C<endpwent>, C<endservent>, C<exec>,
+C<fcntl>, C<flock>, C<fork>, C<getgrent>, C<getgrgid>, C<gethostent>,
+C<getlogin>, C<getnetbyaddr>, C<getnetbyname>, C<getnetent>,
+C<getppid>, C<getprgp>, C<getpriority>, C<getprotobynumber>,
+C<getprotoent>, C<getpwent>, C<getpwnam>, C<getpwuid>,
+C<getservbyport>, C<getservent>, C<getsockopt>, C<glob>, C<ioctl>,
+C<kill>, C<link>, C<lstat>, C<msgctl>, C<msgget>, C<msgrcv>,
+C<msgsnd>, C<open>, C<pipe>, C<readlink>, C<select>, C<semctl>,
+C<semget>, C<semop>, C<setgrent>, C<sethostent>, C<setnetent>,
+C<setpgrp>, C<setpriority>, C<setprotoent>, C<setpwent>,
+C<setservent>, C<setsockopt>, C<shmctl>, C<shmget>, C<shmread>,
+C<shmwrite>, C<socketpair>, C<stat>, C<symlink>, C<syscall>,
+C<sysopen>, C<system>, C<times>, C<truncate>, C<umask>, C<utime>,
+C<wait>, C<waitpid>
+
+For more information about the portability of these functions, see
+L<perlport> and other available platform-specific documentation.
+
=head2 Alphabetical Listing of Perl Functions
=over 8