summaryrefslogtreecommitdiff
path: root/ext/POSIX/lib/POSIX.pm
blob: 98d634d9a0a2e7ce6c035f99ff4bbd1235dcd2f9 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
package POSIX;
use strict;
use warnings;

our ($AUTOLOAD, %SIGRT);

our $VERSION = '1.28_001';

require XSLoader;

use Fcntl qw(FD_CLOEXEC F_DUPFD F_GETFD F_GETFL F_GETLK F_RDLCK F_SETFD
	     F_SETFL F_SETLK F_SETLKW F_UNLCK F_WRLCK O_ACCMODE O_APPEND
	     O_CREAT O_EXCL O_NOCTTY O_NONBLOCK O_RDONLY O_RDWR O_TRUNC
	     O_WRONLY SEEK_CUR SEEK_END SEEK_SET
	     S_ISBLK S_ISCHR S_ISDIR S_ISFIFO S_ISREG
	     S_IRGRP S_IROTH S_IRUSR S_IRWXG S_IRWXO S_IRWXU S_ISGID S_ISUID
	     S_IWGRP S_IWOTH S_IWUSR S_IXGRP S_IXOTH S_IXUSR);

my $loaded;

sub import {
    my $pkg = shift;

    load_imports() unless $loaded++;

    # Grandfather old foo_h form to new :foo_h form
    s/^(?=\w+_h$)/:/ for my @list = @_;

    local $Exporter::ExportLevel = 1;
    Exporter::import($pkg,@list);
}

sub croak { require Carp;  goto &Carp::croak }
sub usage { croak "Usage: POSIX::$_[0]" }

XSLoader::load();

my %replacement = (
    atexit      => 'END {}',
    atof        => undef,
    atoi        => undef,
    atol        => undef,
    bsearch     => \'not supplied',
    calloc      => undef,
    clearerr    => 'IO::Handle::clearerr',
    div         => '/, % and int',
    execl       => undef,
    execle      => undef,
    execlp      => undef,
    execv       => undef,
    execve      => undef,
    execvp      => undef,
    fclose      => 'IO::Handle::close',
    fdopen      => 'IO::Handle::new_from_fd',
    feof        => 'IO::Handle::eof',
    ferror      => 'IO::Handle::error',
    fflush      => 'IO::Handle::flush',
    fgetc       => 'IO::Handle::getc',
    fgetpos     => 'IO::Seekable::getpos',
    fgets       => 'IO::Handle::gets',
    fileno      => 'IO::Handle::fileno',
    fopen       => 'IO::File::open',
    fprintf     => 'printf',
    fputc       => 'print',
    fputs       => 'print',
    fread       => 'read',
    free        => undef,
    freopen     => 'open',
    fscanf      => '<> and regular expressions',
    fseek       => 'IO::Seekable::seek',
    fsetpos     => 'IO::Seekable::setpos',
    fsync       => 'IO::Handle::sync',
    ftell       => 'IO::Seekable::tell',
    fwrite      => 'print',
    labs        => 'abs',
    ldiv        => '/, % and int',
    longjmp     => 'die',
    malloc      => undef,
    memchr      => 'index()',
    memcmp      => 'eq',
    memcpy      => '=',
    memmove     => '=',
    memset      => 'x',
    offsetof    => undef,
    putc        => 'print',
    putchar     => 'print',
    puts        => 'print',
    qsort       => 'sort',
    rand        => \'non-portable, use Perl\'s rand instead',
    realloc     => undef,
    scanf       => '<> and regular expressions',
    setbuf      => 'IO::Handle::setbuf',
    setjmp      => 'eval {}',
    setvbuf     => 'IO::Handle::setvbuf',
    siglongjmp  => 'die',
    sigsetjmp   => 'eval {}',
    srand       => \'not supplied; refer to Perl\'s srand documentation',
    sscanf      => 'regular expressions',
    strcat      => '.=',
    strchr      => 'index()',
    strcmp      => 'eq',
    strcpy      => '=',
    strcspn     => 'regular expressions',
    strlen      => 'length',
    strncat     => '.=',
    strncmp     => 'eq',
    strncpy     => '=',
    strpbrk     => undef,
    strrchr     => 'rindex()',
    strspn      => undef,
    strtok      => undef,
    tmpfile     => 'IO::File::new_tmpfile',
    ungetc      => 'IO::Handle::ungetc',
    vfprintf    => undef,
    vprintf     => undef,
    vsprintf    => undef,
);

my %reimpl = (
    assert    => 'expr => croak "Assertion failed" if !$_[0]',
    tolower   => 'string => lc($_[0])',
    toupper   => 'string => uc($_[0])',
    closedir  => 'dirhandle => CORE::closedir($_[0])',
    opendir   => 'directory => my $dh; CORE::opendir($dh, $_[0]) ? $dh : undef',
    readdir   => 'dirhandle => CORE::readdir($_[0])',
    rewinddir => 'dirhandle => CORE::rewinddir($_[0])',
    errno     => '$! + 0',
    creat     => 'filename, mode => &open($_[0], &O_WRONLY | &O_CREAT | &O_TRUNC, $_[1])',
    fcntl     => 'filehandle, cmd, arg => CORE::fcntl($_[0], $_[1], $_[2])',
    getgrgid  => 'gid => CORE::getgrgid($_[0])',
    getgrnam  => 'name => CORE::getgrnam($_[0])',
    atan2     => 'x, y => CORE::atan2($_[0], $_[1])',
    cos       => 'x => CORE::cos($_[0])',
    exp       => 'x => CORE::exp($_[0])',
    fabs      => 'x => CORE::abs($_[0])',
    log       => 'x => CORE::log($_[0])',
    pow       => 'x, exponent => $_[0] ** $_[1]',
    sin       => 'x => CORE::sin($_[0])',
    sqrt      => 'x => CORE::sqrt($_[0])',
    getpwnam  => 'name => CORE::getpwnam($_[0])',
    getpwuid  => 'uid => CORE::getpwuid($_[0])',
    kill      => 'pid, sig => CORE::kill $_[1], $_[0]',
    raise     => 'sig => CORE::kill $_[0], $$;	# Is this good enough',
    getc      => 'handle => CORE::getc($_[0])',
    getchar   => 'CORE::getc(STDIN)',
    gets      => 'scalar <STDIN>',
    remove    => 'filename => (-d $_[0]) ? CORE::rmdir($_[0]) : CORE::unlink($_[0])',
    rename    => 'oldfilename, newfilename => CORE::rename($_[0], $_[1])',
    rewind    => 'filehandle => CORE::seek($_[0],0,0)',
    abs       => 'x => CORE::abs($_[0])',
    exit      => 'status => CORE::exit($_[0])',
    getenv    => 'name => $ENV{$_[0]}',
    system    => 'command => CORE::system($_[0])',
    strerror  => 'errno => local $! = $_[0]; "$!"',
    strstr    => 'big, little => CORE::index($_[0], $_[1])',
    chmod     => 'mode, filename => CORE::chmod($_[0], $_[1])',
    fstat     => 'fd => CORE::open my $dup, "<&", $_[0]; CORE::stat($dup)', # Gross.
    mkdir     => 'directoryname, mode => CORE::mkdir($_[0], $_[1])',
    stat      => 'filename => CORE::stat($_[0])',
    umask     => 'mask => CORE::umask($_[0])',
    wait      => 'CORE::wait()',
    waitpid   => 'pid, options => CORE::waitpid($_[0], $_[1])',
    gmtime    => 'time => CORE::gmtime($_[0])',
    localtime => 'time => CORE::localtime($_[0])',
    time      => 'CORE::time',
    alarm     => 'seconds => CORE::alarm($_[0])',
    chdir     => 'directory => CORE::chdir($_[0])',
    chown     => 'uid, gid, filename => CORE::chown($_[0], $_[1], $_[2])',
    fork      => 'CORE::fork',
    getegid   => '$) + 0',
    geteuid   => '$> + 0',
    getgid    => '$( + 0',
    getgroups => 'my %seen; grep !$seen{$_}++, split " ", $)',
    getlogin  => 'CORE::getlogin()',
    getpgrp   => 'CORE::getpgrp',
    getpid    => '$$',
    getppid   => 'CORE::getppid',
    getuid    => '$<',
    isatty    => 'filehandle => -t $_[0]',
    link      => 'oldfilename, newfilename => CORE::link($_[0], $_[1])',
    rmdir     => 'directoryname => CORE::rmdir($_[0])',
    unlink    => 'filename => CORE::unlink($_[0])',
    utime     => 'filename, atime, mtime => CORE::utime($_[1], $_[2], $_[0])',
);

eval join ';', map "sub $_", keys %replacement, keys %reimpl;

sub AUTOLOAD {
    my ($func) = ($AUTOLOAD =~ /.*::(.*)/);

    if (my $code = $reimpl{$func}) {
	my ($num, $arg) = (0, '');
	if ($code =~ s/^(.*?) *=> *//) {
	    $arg = $1;
	    $num = 1 + $arg =~ tr/,//;
	}
	# no warnings to be consistent with the old implementation, where each
	# function was in its own little AutoSplit world:
	eval qq{ sub $func {
		no warnings;
		usage "$func($arg)" if \@_ != $num;
		$code
	    } };
	no strict;
	goto &$AUTOLOAD;
    }
    if (exists $replacement{$func}) {
	my $how = $replacement{$func};
	croak "Unimplemented: POSIX::$func() is C-specific, stopped"
	    unless defined $how;
	croak "Unimplemented: POSIX::$func() is $$how" if ref $how;
	croak "Use method $how() instead of POSIX::$func()" if $how =~ /::/;
	croak "Unimplemented: POSIX::$func() is C-specific: use $how instead";
    }

    constant($func);
}

sub perror {
    print STDERR "@_: " if @_;
    print STDERR $!,"\n";
}

sub printf {
    usage "printf(pattern, args...)" if @_ < 1;
    CORE::printf STDOUT @_;
}

sub sprintf {
    usage "sprintf(pattern, args...)" if @_ == 0;
    CORE::sprintf(shift,@_);
}

sub load_imports {
our %EXPORT_TAGS = (

    assert_h =>	[qw(assert NDEBUG)],

    ctype_h =>	[qw(isalnum isalpha iscntrl isdigit isgraph islower
		isprint ispunct isspace isupper isxdigit tolower toupper)],

    dirent_h =>	[],

    errno_h =>	[qw(E2BIG EACCES EADDRINUSE EADDRNOTAVAIL EAFNOSUPPORT
		EAGAIN EALREADY EBADF EBUSY ECHILD ECONNABORTED
		ECONNREFUSED ECONNRESET EDEADLK EDESTADDRREQ EDOM EDQUOT
		EEXIST EFAULT EFBIG EHOSTDOWN EHOSTUNREACH EINPROGRESS
		EINTR EINVAL EIO EISCONN EISDIR ELOOP EMFILE EMLINK
		EMSGSIZE ENAMETOOLONG ENETDOWN ENETRESET ENETUNREACH
		ENFILE ENOBUFS ENODEV ENOENT ENOEXEC ENOLCK ENOMEM
		ENOPROTOOPT ENOSPC ENOSYS ENOTBLK ENOTCONN ENOTDIR
		ENOTEMPTY ENOTSOCK ENOTTY ENXIO EOPNOTSUPP EPERM
		EPFNOSUPPORT EPIPE EPROCLIM EPROTONOSUPPORT EPROTOTYPE
		ERANGE EREMOTE ERESTART EROFS ESHUTDOWN ESOCKTNOSUPPORT
		ESPIPE ESRCH ESTALE ETIMEDOUT ETOOMANYREFS ETXTBSY
		EUSERS EWOULDBLOCK EXDEV errno)],

    fcntl_h =>	[qw(FD_CLOEXEC F_DUPFD F_GETFD F_GETFL F_GETLK F_RDLCK
		F_SETFD F_SETFL F_SETLK F_SETLKW F_UNLCK F_WRLCK
		O_ACCMODE O_APPEND O_CREAT O_EXCL O_NOCTTY O_NONBLOCK
		O_RDONLY O_RDWR O_TRUNC O_WRONLY
		creat
		SEEK_CUR SEEK_END SEEK_SET
		S_IRGRP S_IROTH S_IRUSR S_IRWXG S_IRWXO S_IRWXU
		S_ISBLK S_ISCHR S_ISDIR S_ISFIFO S_ISGID S_ISREG S_ISUID
		S_IWGRP S_IWOTH S_IWUSR)],

    float_h =>	[qw(DBL_DIG DBL_EPSILON DBL_MANT_DIG
		DBL_MAX DBL_MAX_10_EXP DBL_MAX_EXP
		DBL_MIN DBL_MIN_10_EXP DBL_MIN_EXP
		FLT_DIG FLT_EPSILON FLT_MANT_DIG
		FLT_MAX FLT_MAX_10_EXP FLT_MAX_EXP
		FLT_MIN FLT_MIN_10_EXP FLT_MIN_EXP
		FLT_RADIX FLT_ROUNDS
		LDBL_DIG LDBL_EPSILON LDBL_MANT_DIG
		LDBL_MAX LDBL_MAX_10_EXP LDBL_MAX_EXP
		LDBL_MIN LDBL_MIN_10_EXP LDBL_MIN_EXP)],

    grp_h =>	[],

    limits_h =>	[qw( ARG_MAX CHAR_BIT CHAR_MAX CHAR_MIN CHILD_MAX
		INT_MAX INT_MIN LINK_MAX LONG_MAX LONG_MIN MAX_CANON
		MAX_INPUT MB_LEN_MAX NAME_MAX NGROUPS_MAX OPEN_MAX
		PATH_MAX PIPE_BUF SCHAR_MAX SCHAR_MIN SHRT_MAX SHRT_MIN
		SSIZE_MAX STREAM_MAX TZNAME_MAX UCHAR_MAX UINT_MAX
		ULONG_MAX USHRT_MAX _POSIX_ARG_MAX _POSIX_CHILD_MAX
		_POSIX_LINK_MAX _POSIX_MAX_CANON _POSIX_MAX_INPUT
		_POSIX_NAME_MAX _POSIX_NGROUPS_MAX _POSIX_OPEN_MAX
		_POSIX_PATH_MAX _POSIX_PIPE_BUF _POSIX_SSIZE_MAX
		_POSIX_STREAM_MAX _POSIX_TZNAME_MAX)],

    locale_h =>	[qw(LC_ALL LC_COLLATE LC_CTYPE LC_MESSAGES
		    LC_MONETARY LC_NUMERIC LC_TIME NULL
		    localeconv setlocale)],

    math_h =>	[qw(HUGE_VAL acos asin atan ceil cosh fabs floor fmod
		frexp ldexp log10 modf pow sinh tan tanh)],

    pwd_h =>	[],

    setjmp_h =>	[qw(longjmp setjmp siglongjmp sigsetjmp)],

    signal_h =>	[qw(SA_NOCLDSTOP SA_NOCLDWAIT SA_NODEFER SA_ONSTACK
		SA_RESETHAND SA_RESTART SA_SIGINFO SIGABRT SIGALRM
		SIGCHLD SIGCONT SIGFPE SIGHUP SIGILL SIGINT SIGKILL
		SIGPIPE %SIGRT SIGRTMIN SIGRTMAX SIGQUIT SIGSEGV SIGSTOP
		SIGTERM SIGTSTP SIGTTIN SIGTTOU SIGUSR1 SIGUSR2 SIGBUS
		SIGPOLL SIGPROF SIGSYS SIGTRAP SIGURG SIGVTALRM SIGXCPU SIGXFSZ
		SIG_BLOCK SIG_DFL SIG_ERR SIG_IGN SIG_SETMASK SIG_UNBLOCK
		raise sigaction signal sigpending sigprocmask sigsuspend)],

    stdarg_h =>	[],

    stddef_h =>	[qw(NULL offsetof)],

    stdio_h =>	[qw(BUFSIZ EOF FILENAME_MAX L_ctermid L_cuserid
		L_tmpname NULL SEEK_CUR SEEK_END SEEK_SET
		STREAM_MAX TMP_MAX stderr stdin stdout
		clearerr fclose fdopen feof ferror fflush fgetc fgetpos
		fgets fopen fprintf fputc fputs fread freopen
		fscanf fseek fsetpos ftell fwrite getchar gets
		perror putc putchar puts remove rewind
		scanf setbuf setvbuf sscanf tmpfile tmpnam
		ungetc vfprintf vprintf vsprintf)],

    stdlib_h =>	[qw(EXIT_FAILURE EXIT_SUCCESS MB_CUR_MAX NULL RAND_MAX
		abort atexit atof atoi atol bsearch calloc div
		free getenv labs ldiv malloc mblen mbstowcs mbtowc
		qsort realloc strtod strtol strtoul wcstombs wctomb)],

    string_h =>	[qw(NULL memchr memcmp memcpy memmove memset strcat
		strchr strcmp strcoll strcpy strcspn strerror strlen
		strncat strncmp strncpy strpbrk strrchr strspn strstr
		strtok strxfrm)],

    sys_stat_h => [qw(S_IRGRP S_IROTH S_IRUSR S_IRWXG S_IRWXO S_IRWXU
		S_ISBLK S_ISCHR S_ISDIR S_ISFIFO S_ISGID S_ISREG
		S_ISUID S_IWGRP S_IWOTH S_IWUSR S_IXGRP S_IXOTH S_IXUSR
		fstat mkfifo)],

    sys_times_h => [],

    sys_types_h => [],

    sys_utsname_h => [qw(uname)],

    sys_wait_h => [qw(WEXITSTATUS WIFEXITED WIFSIGNALED WIFSTOPPED
		WNOHANG WSTOPSIG WTERMSIG WUNTRACED)],

    termios_h => [qw( B0 B110 B1200 B134 B150 B1800 B19200 B200 B2400
		B300 B38400 B4800 B50 B600 B75 B9600 BRKINT CLOCAL
		CREAD CS5 CS6 CS7 CS8 CSIZE CSTOPB ECHO ECHOE ECHOK
		ECHONL HUPCL ICANON ICRNL IEXTEN IGNBRK IGNCR IGNPAR
		INLCR INPCK ISIG ISTRIP IXOFF IXON NCCS NOFLSH OPOST
		PARENB PARMRK PARODD TCIFLUSH TCIOFF TCIOFLUSH TCION
		TCOFLUSH TCOOFF TCOON TCSADRAIN TCSAFLUSH TCSANOW
		TOSTOP VEOF VEOL VERASE VINTR VKILL VMIN VQUIT VSTART
		VSTOP VSUSP VTIME
		cfgetispeed cfgetospeed cfsetispeed cfsetospeed tcdrain
		tcflow tcflush tcgetattr tcsendbreak tcsetattr )],

    time_h =>	[qw(CLK_TCK CLOCKS_PER_SEC NULL asctime clock ctime
		difftime mktime strftime strptime tzset tzname)],

    unistd_h =>	[qw(F_OK NULL R_OK SEEK_CUR SEEK_END SEEK_SET
		STDERR_FILENO STDIN_FILENO STDOUT_FILENO W_OK X_OK
		_PC_CHOWN_RESTRICTED _PC_LINK_MAX _PC_MAX_CANON
		_PC_MAX_INPUT _PC_NAME_MAX _PC_NO_TRUNC _PC_PATH_MAX
		_PC_PIPE_BUF _PC_VDISABLE _POSIX_CHOWN_RESTRICTED
		_POSIX_JOB_CONTROL _POSIX_NO_TRUNC _POSIX_SAVED_IDS
		_POSIX_VDISABLE _POSIX_VERSION _SC_ARG_MAX
		_SC_CHILD_MAX _SC_CLK_TCK _SC_JOB_CONTROL
		_SC_NGROUPS_MAX _SC_OPEN_MAX _SC_PAGESIZE _SC_SAVED_IDS
		_SC_STREAM_MAX _SC_TZNAME_MAX _SC_VERSION
		_exit access ctermid cuserid
		dup2 dup execl execle execlp execv execve execvp
		fpathconf fsync getcwd getegid geteuid getgid getgroups
		getpid getuid isatty lseek pathconf pause setgid setpgid
		setsid setuid sysconf tcgetpgrp tcsetpgrp ttyname)],

    utime_h =>	[],
);

# Exporter::export_tags();
{
  # De-duplicate the export list: 
  my %export;
  @export{map {@$_} values %EXPORT_TAGS} = ();

  our @EXPORT_OK = (qw(close lchown nice open pipe read sleep times write
		       printf sprintf),
		    grep {!exists $export{$_}} keys %reimpl, keys %replacement);

  # Symbols that should not be exported by default because they are recently
  # added. It would upset too much of CPAN to export these by default
  delete $export{$_} and push @EXPORT_OK, $_ for qw(strptime);

  # Doing the de-dup with a temporary hash has the advantage that the SVs in
  # @EXPORT are actually shared hash key scalars, which will save some memory.
  our @EXPORT = keys %export;
}

require Exporter;
}

package POSIX::SigAction;

sub new { bless {HANDLER => $_[1], MASK => $_[2], FLAGS => $_[3] || 0, SAFE => 0}, $_[0] }
sub handler { $_[0]->{HANDLER} = $_[1] if @_ > 1; $_[0]->{HANDLER} };
sub mask    { $_[0]->{MASK}    = $_[1] if @_ > 1; $_[0]->{MASK} };
sub flags   { $_[0]->{FLAGS}   = $_[1] if @_ > 1; $_[0]->{FLAGS} };
sub safe    { $_[0]->{SAFE}    = $_[1] if @_ > 1; $_[0]->{SAFE} };

{
package POSIX::SigSet;
# This package is here entirely to make sure that POSIX::SigSet is seen by the
# PAUSE indexer, so that it will always be clearly indexed in core.  This is to
# prevent the accidental case where a third-party distribution can accidentally
# claim the POSIX::SigSet package, as occurred in 2011-12. -- rjbs, 2011-12-30
}

package POSIX::SigRt;

require Tie::Hash;

our @ISA = 'Tie::StdHash';

our ($_SIGRTMIN, $_SIGRTMAX, $_sigrtn);

our $SIGACTION_FLAGS = 0;

sub _init {
    $_SIGRTMIN = &POSIX::SIGRTMIN;
    $_SIGRTMAX = &POSIX::SIGRTMAX;
    $_sigrtn   = $_SIGRTMAX - $_SIGRTMIN;
}

sub _croak {
    &_init unless defined $_sigrtn;
    die "POSIX::SigRt not available" unless defined $_sigrtn && $_sigrtn > 0;
}

sub _getsig {
    &_croak;
    my $rtsig = $_[0];
    # Allow (SIGRT)?MIN( + n)?, a common idiom when doing these things in C.
    $rtsig = $_SIGRTMIN + ($1 || 0)
	if $rtsig =~ /^(?:(?:SIG)?RT)?MIN(\s*\+\s*(\d+))?$/;
    return $rtsig;
}

sub _exist {
    my $rtsig = _getsig($_[1]);
    my $ok    = $rtsig >= $_SIGRTMIN && $rtsig <= $_SIGRTMAX;
    ($rtsig, $ok);
}

sub _check {
    my ($rtsig, $ok) = &_exist;
    die "No POSIX::SigRt signal $_[1] (valid range SIGRTMIN..SIGRTMAX, or $_SIGRTMIN..$_SIGRTMAX)"
	unless $ok;
    return $rtsig;
}

sub new {
    my ($rtsig, $handler, $flags) = @_;
    my $sigset = POSIX::SigSet->new($rtsig);
    my $sigact = POSIX::SigAction->new($handler, $sigset, $flags);
    POSIX::sigaction($rtsig, $sigact);
}

sub EXISTS { &_exist }
sub FETCH  { my $rtsig = &_check;
	     my $oa = POSIX::SigAction->new();
	     POSIX::sigaction($rtsig, undef, $oa);
	     return $oa->{HANDLER} }
sub STORE  { my $rtsig = &_check; new($rtsig, $_[2], $SIGACTION_FLAGS) }
sub DELETE { delete $SIG{ &_check } }
sub CLEAR  { &_exist; delete @SIG{ &POSIX::SIGRTMIN .. &POSIX::SIGRTMAX } }
sub SCALAR { &_croak; $_sigrtn + 1 }

tie %POSIX::SIGRT, 'POSIX::SigRt';
# and the expression on the line above is true, so we return true.