perlport.pod

ARM上的如果你对底层感兴趣

Not implemented. (S<Mac OS>, Win32)

Not useful. (S<RISC OS>)

=item getgrgid GID

Not implemented. (S<Mac OS>, Win32, VMS, S<RISC OS>)

=item getnetbyaddr ADDR,ADDRTYPE

Not implemented. (S<Mac OS>, Win32, Plan9)

=item getprotobynumber NUMBER

Not implemented. (S<Mac OS>)

=item getservbyport PORT,PROTO

Not implemented. (S<Mac OS>)

=item getpwent

Not implemented. (S<Mac OS>, Win32)

=item getgrent

Not implemented. (S<Mac OS>, Win32, VMS)

=item gethostent

Not implemented. (S<Mac OS>, Win32)

=item getnetent

Not implemented. (S<Mac OS>, Win32, Plan9)

=item getprotoent

Not implemented. (S<Mac OS>, Win32, Plan9)

=item getservent

Not implemented. (Win32, Plan9)

=item setpwent

Not implemented. (S<Mac OS>, Win32, S<RISC OS>)

=item setgrent

Not implemented. (S<Mac OS>, Win32, VMS, S<RISC OS>)

=item sethostent STAYOPEN

Not implemented. (S<Mac OS>, Win32, Plan9, S<RISC OS>)

=item setnetent STAYOPEN

Not implemented. (S<Mac OS>, Win32, Plan9, S<RISC OS>)

=item setprotoent STAYOPEN

Not implemented. (S<Mac OS>, Win32, Plan9, S<RISC OS>)

=item setservent STAYOPEN

Not implemented. (Plan9, Win32, S<RISC OS>)

=item endpwent

Not implemented. (S<Mac OS>, Win32)

=item endgrent

Not implemented. (S<Mac OS>, Win32, VMS, S<RISC OS>)

=item endhostent

Not implemented. (S<Mac OS>, Win32)

=item endnetent

Not implemented. (S<Mac OS>, Win32, Plan9)

=item endprotoent

Not implemented. (S<Mac OS>, Win32, Plan9)

=item endservent

Not implemented. (Plan9, Win32)

=item getsockopt SOCKET,LEVEL,OPTNAME

Not implemented. (S<Mac OS>, Plan9)

=item glob EXPR

=item glob

Globbing built-in, but only C<*> and C<?> metacharacters are supported.
(S<Mac OS>)

Features depend on external perlglob.exe or perlglob.bat. May be
overridden with something like File::DosGlob, which is recommended.
(Win32)

Globbing built-in, but only C<*> and C<?> metacharacters are supported.
Globbing relies on operating system calls, which may return filenames
in any order.  As most filesystems are case-insensitive, even "sorted"
filenames will not be in case-sensitive order. (S<RISC OS>)

=item ioctl FILEHANDLE,FUNCTION,SCALAR

Not implemented. (VMS)

Available only for socket handles, and it does what the ioctlsocket() call
in the Winsock API does. (Win32)

Available only for socket handles. (S<RISC OS>)

=item kill LIST

Not implemented, hence not useful for taint checking. (S<Mac OS>,
S<RISC OS>)

Available only for process handles returned by the C<system(1, ...)>
method of spawning a process. (Win32)

=item link OLDFILE,NEWFILE

Not implemented. (S<Mac OS>, Win32, VMS, S<RISC OS>)

=item lstat FILEHANDLE

=item lstat EXPR

=item lstat

Not implemented. (VMS, S<RISC OS>)

Return values may be bogus. (Win32)

=item msgctl ID,CMD,ARG

=item msgget KEY,FLAGS

=item msgsnd ID,MSG,FLAGS

=item msgrcv ID,VAR,SIZE,TYPE,FLAGS

Not implemented. (S<Mac OS>, Win32, VMS, Plan9, S<RISC OS>)

=item open FILEHANDLE,EXPR

=item open FILEHANDLE

The C<|> variants are only supported if ToolServer is installed.
(S<Mac OS>)

open to C<|-> and C<-|> are unsupported. (S<Mac OS>, Win32, S<RISC OS>)

=item pipe READHANDLE,WRITEHANDLE

Not implemented. (S<Mac OS>)

=item readlink EXPR

=item readlink

Not implemented. (Win32, VMS, S<RISC OS>)

=item select RBITS,WBITS,EBITS,TIMEOUT

Only implemented on sockets. (Win32)

Only reliable on sockets. (S<RISC OS>)

=item semctl ID,SEMNUM,CMD,ARG

=item semget KEY,NSEMS,FLAGS

=item semop KEY,OPSTRING

Not implemented. (S<Mac OS>, Win32, VMS, S<RISC OS>)

=item setpgrp PID,PGRP

Not implemented. (S<Mac OS>, Win32, VMS, S<RISC OS>)

=item setpriority WHICH,WHO,PRIORITY

Not implemented. (S<Mac OS>, Win32, VMS, S<RISC OS>)

=item setsockopt SOCKET,LEVEL,OPTNAME,OPTVAL

Not implemented. (S<Mac OS>, Plan9)

=item shmctl ID,CMD,ARG

=item shmget KEY,SIZE,FLAGS

=item shmread ID,VAR,POS,SIZE

=item shmwrite ID,STRING,POS,SIZE

Not implemented. (S<Mac OS>, Win32, VMS, S<RISC OS>)

=item socketpair SOCKET1,SOCKET2,DOMAIN,TYPE,PROTOCOL

Not implemented. (S<Mac OS>, Win32, VMS, S<RISC OS>)

=item stat FILEHANDLE

=item stat EXPR

=item stat

mtime and atime are the same thing, and ctime is creation time instead of
inode change time. (S<Mac OS>)

device and inode are not meaningful.  (Win32)

device and inode are not necessarily reliable.  (VMS)

mtime, atime and ctime all return the last modification time.  Device and
inode are not necessarily reliable.  (S<RISC OS>)

=item symlink OLDFILE,NEWFILE

Not implemented. (Win32, VMS, S<RISC OS>)

=item syscall LIST

Not implemented. (S<Mac OS>, Win32, VMS, S<RISC OS>)

=item sysopen FILEHANDLE,FILENAME,MODE,PERMS

The traditional "0", "1", and "2" MODEs are implemented with different
numeric values on some systems.  The flags exported by C<Fcntl>
(O_RDONLY, O_WRONLY, O_RDWR) should work everywhere though.  (S<Mac
OS>, OS/390)

=item system LIST

Only implemented if ToolServer is installed. (S<Mac OS>)

As an optimization, may not call the command shell specified in
C<$ENV{PERL5SHELL}>. C<system(1, @args)> spawns an external
process and immediately returns its process designator, without
waiting for it to terminate.  Return value may be used subsequently
in C<wait> or C<waitpid>.  (Win32)

There is no shell to process metacharacters, and the native standard is
to pass a command line terminated by "\n" "\r" or "\0" to the spawned
program.  Redirection such as C<E<gt> foo> is performed (if at all) by
the run time library of the spawned program.  C<system> I<list> will call
the Unix emulation library's C<exec> emulation, which attempts to provide
emulation of the stdin, stdout, stderr in force in the parent, providing
the child program uses a compatible version of the emulation library.
I<scalar> will call the native command line direct and no such emulation
of a child Unix program will exists.  Mileage B<will> vary.  (S<RISC OS>)

=item times

Only the first entry returned is nonzero. (S<Mac OS>)

"cumulative" times will be bogus.  On anything other than Windows NT,
"system" time will be bogus, and "user" time is actually the time
returned by the clock() function in the C runtime library. (Win32)

Not useful. (S<RISC OS>)

=item truncate FILEHANDLE,LENGTH

=item truncate EXPR,LENGTH

Not implemented. (VMS)

=item umask EXPR

=item umask

Returns undef where unavailable, as of version 5.005.

=item utime LIST

Only the modification time is updated. (S<Mac OS>, VMS, S<RISC OS>)

May not behave as expected.  Behavior depends on the C runtime
library's implementation of utime(), and the filesystem being
used.  The FAT filesystem typically does not support an "access
time" field, and it may limit timestamps to a granularity of
two seconds. (Win32)

=item wait

=item waitpid PID,FLAGS

Not implemented. (S<Mac OS>)

Can only be applied to process handles returned for processes spawned
using C<system(1, ...)>. (Win32)

Not useful. (S<RISC OS>)

=back

=head1 CHANGES

=over 4

=item 1.33, 06 August 1998

Integrate more minor changes.

=item 1.32, 05 August 1998

Integrate more minor changes.

=item 1.30, 03 August 1998

Major update for RISC OS, other minor changes.

=item 1.23, 10 July 1998

First public release with perl5.005.

=back

=head1 AUTHORS / CONTRIBUTORS

Abigail E<lt>[e-mail]<gt>,
Charles Bailey E<lt>[e-mail]<gt>,
Graham Barr E<lt>[e-mail]<gt>,
Tom Christiansen E<lt>[e-mail]<gt>,
Nicholas Clark E<lt>[e-mail]<gt>,
Andy Dougherty E<lt>[e-mail]<gt>,
Dominic Dunlop E<lt>[e-mail]<gt>,
M.J.T. Guy E<lt>[e-mail]<gt>,
Luther Huffman E<lt>[e-mail]<gt>,
Nick Ing-Simmons E<lt>[e-mail]<gt>,
Andreas J. KE<ouml>nig E<lt>[e-mail]<gt>,
Andrew M. Langmead E<lt>[e-mail]<gt>,
Paul Moore E<lt>[e-mail]<gt>,
Chris Nandor E<lt>[e-mail]<gt>,
Matthias Neeracher E<lt>[e-mail]<gt>,
Gary Ng E<lt>[e-mail]<gt>,
Tom Phoenix E<lt>[e-mail]<gt>,
Peter Prymmer E<lt>[e-mail]<gt>,
Hugo van der Sanden E<lt>[e-mail]<gt>,
Gurusamy Sarathy E<lt>[e-mail]<gt>,
Paul J. Schinder E<lt>[e-mail]<gt>,
Dan Sugalski E<lt>[e-mail]<gt>,
Nathan Torkington E<lt>[e-mail]<gt>.

This document is maintained by Chris Nandor.

=head1 VERSION

Version 1.34, last modified 07 August 1998.