perl核心模块解析（一） ? ?POSIX
详细文档链接如下
源自：http://blog.csdn.net/jonathanxqs
转自：http://perldoc.perl.org/POSIX.html
? POSIX,是可移植操作系统接口（Portable Operating System Interface ），POSIX标准定义了操作系统应该为应用程序提供的接口标准，是IEEE为要在各种UNIX操作系统上运行的软件而定义的一系列API标准的总称，其正式称呼为IEEE 1003，而国际标准名称为ISO/IEC 9945。
POSIX标准意在期望获得源代码级别的软件可移植性。换句话说，为一个POSIX兼容的操作系统编写的程序，应该可以在任何其它的POSIX操作系统（即使是来自另一个厂商）上编译执行。
POSIX 并不局限于 UNIX。许多其它的操作系统，例如 DEC OpenVMS 支持 POSIX 标准，尤其是 IEEE Std. 1003.1-1990（1995 年修订）或 POSIX.1，POSIX.1 提供了源代码级别的 C 语言应用编程接口（API）给操作系统的服务程序，例如读写文件。POSIX.1 已经被国际标准化组织（International Standards Organization，ISO）所接受，被命名为 ISO/IEC 9945-1:1990 标准。
POSIX
- NAME
- SYNOPSIS
- DESCRIPTION
- CAVEATS
- FUNCTIONS
-
CLASSES
- POSIX::SigAction
- POSIX::SigRt
- POSIX::SigSet
- POSIX::Termios
- PATHNAME CONSTANTS
- POSIX CONSTANTS
- SYSTEM CONFIGURATION
- ERRNO
- FCNTL
- FLOAT
- FLOATING-POINT ENVIRONMENT
- LIMITS
- LOCALE
- MATH
- SIGNAL
- STAT
- STDLIB
- STDIO
- TIME
- UNISTD
- WAIT
NAME
POSIX - Perl interface to IEEE Std 1003.1
SYNOPSIS
- use POSIX ();
- POSIX qw(setsid)qw(:errno_h :fcntl_h)
- printf "EINTR is %dn", EINTR $sess_id = POSIX::setsid$fd = POSIX::open($pathO_CREAT|O_EXCL|O_WRONLY0644 # note: that's a filedescriptor,*NOT* a filehandle
DESCRIPTION
The POSIX module permits you to access all (or nearly all) the standard POSIX 1003.1 identifiers. Many of these identifiers have been given Perl-ish interfaces.
This document gives a condensed list of the features available in the POSIX module. Consult your operating system's manpages for general information on most features. Consult?perlfunc?for functions which are noted as being identical to Perl's builtin functions.
The first section describes POSIX functions from the 1003.1 specification. The second section describes some classes for signal objects,TTY objects,and other miscellaneous objects. The remaining sections list various constants and macros in an organization which roughly follows IEEE Std 1003.1b-1993.
CAVEATS
Everything is exported by default?(with a handful of exceptions). This is an unfortunate backwards compatibility feature and its use is?strongly?discouraged. You should either prevent the exporting (by saying?use?POSIX?;?,as usual) and then use fully qualified names (e.g.?POSIX::SEEK_END?),or give an explicit import list. If you do neither and opt for the default (as in?POSIX;?),you will import?hundreds and hundreds?of symbols into your namespace.
A few functions are not implemented because they are C specific. If you attempt to call these,they will print a message telling you that they aren't implemented,and suggest using the Perl equivalent,should one exist. For example,trying to access the?setjmp)?call will elicit the message ")?is?C-specific:?use?eval?{}?instead?".
Furthermore,some evil vendors will claim 1003.1 compliance,but in fact are not so: they will not pass the PCTS (POSIX Compliance Test Suites). For example,one vendor may not define?EDEADLK?,or the semantics of the errno values set by?open(2)?might not be quite right. Perl does not attempt to verify POSIX compliance. That means you can currently successfully say "use POSIX",and then later in your program you find that your vendor has been lax and there's no usable?ICANON?macro after all. This could be construed to be a bug.
FUNCTIONS
-
_exit This is identical to the C function?_exit)?. It exits the program immediately which means among other things buffered I/O is?not?flushed.
Note that when using threads and in Linux this is?not?a good way to exit a thread because in Linux processes and threads are kind of the same thing (Note: while this is the situation in early 2003 there are projects under way to have threads with more POSIXly semantics in Linux). If you want not to return from a thread,detach the thread.
-
abort This is identical to the C function?abort)?. It terminates the process with a?SIGABRT?signal unless caught by a signal handler or if the handler does not return normally (it e.g. does a?longjmp?).
-
abs This is identical to Perl's builtin?abs()?function,returning the absolute value of its numerical argument.
-
access Determines the accessibility of a file.
if( POSIX::access( "/"&POSIX::R_OK ) ){
- print "have read permissionn";
- }
Returns?undef?on failure. Note: do not use?access)?for security purposes. Between the?)?call and the operation you are preparing for the permissions might change: a classic?race condition.
-
acos This is identical to the C function?acos)?,returning the arcus cosine of its numerical argument. See alsoMath::Trig.
-
acosh This is identical to the C function?acosh
alarm This is identical to Perl's builtin?alarm()?function,either for arming or disarming the?SIGARLM
?timer.
-
asctime This is identical to the C function?asctime)?. It returns a string of the form
"Fri Jun 2 18:22:13 2000n "
and it is called thusly
$asctime = $sec$min$hour$mday$mon$year$wday$yday$isdst;
The?$mon?is zero-based: January equals?0?. The?$year?is 1900-based: 2001 equals?101?.?$wday?and?$ydaydefault to zero (and are usually ignored anyway),and?$isdst?defaults to -1.
asin This is identical to the C function?asin
asinh
This is identical to the C function?asinh
assert
Unimplemented,but you can use?die?and the?Carp?module to achieve similar things.
atan This is identical to the C function?atan
atanh
This is identical to the C function?atanh
atan2 This is identical to Perl's builtin?atan2()?function,returning the arcus tangent defined by its two numerical arguments,the?y?coordinate and the?x?coordinate. See also?Math::Trig.
atexit Not implemented.?atexit)?is C-specific: use?END?}?instead,see?perlmod.
atof Not implemented.?atof)?is C-specific. Perl converts strings to numbers transparently. If you need to force a scalar to a number,add a zero to it.
atoi Not implemented.?atoi
atol
Not implemented.?atolint.
bsearch bsearch)?not supplied. For doing binary search on wordlists,see?Search::Dict.
calloc Not implemented.?calloc)?is C-specific. Perl does memory management transparently.
cbrt The cube root [C99].
ceil This is identical to the C function?ceil
chdir This is identical to Perl's builtin?chdir()?function,allowing one to change the working (default) directory,seechdir.
chmod This is identical to Perl's builtin?chmod()?function,allowing one to change file and directory permissions,seechmod.
chown This is identical to Perl's builtin?chown()?function,allowing one to change file and directory owners and groups,see?chown.
clearerr Not implemented. Use the method?IO::Handle::clearerr)?instead,to reset the error state (if any) and EOF state (if any) of the given stream.
clock This is identical to the C function?clock
close Close the file. This uses file descriptors such as those obtained by calling?POSIX::open
?.
"foo"&POSIX::O_RDONLY POSIX::close$fd ;
Returns?undef?on failure.
See also?close.
closedir This is identical to Perl's builtin?closedir()?function for closing a directory handle,see?closedir.
cos This is identical to Perl's builtin?cos()?function,for returning the cosine of its numerical argument,see?cos. See also?Math::Trig.
cosh This is identical to the C function?cosh
copysign
Returns?x?but with the sign of?y?[C99].
$x_with_sign_of_y = POSIX::copysign$x$y;
See also?signbit.
creat Create a new file. This returns a file descriptor like the ones returned by?POSIX::open?. Use?POSIX::close?to close the file.
POSIX::creat0611 ;
See also?sysopen?and its?O_CREAT?flag.
ctermid Generates the path name for the controlling terminal.
$path = POSIX::ctermid;
ctime This is identical to the C function?ctime)?and equivalent to?(localtime(...
cuserid
Get the login name of the owner of the current process.
$name = POSIX::cuserid;
difftime This is identical to the C function?difftimetime()),see?time.
div Not implemented.?div)?is C-specific,use?int?on the usual?/?division and the modulus?%?.
dup This is similar to the C function?dup This uses file descriptors such as those obtained by calling?POSIX::open?.
Returns?undef?on failure.
dup2 This is similar to the C function?dup2 This uses file descriptors such as those obtained by calling?undef?on failure.
erf The error function [C99].
erfc The complementary error function [C99].
errno Returns the value of errno.
$errno = POSIX::errno;
This identical to the numerical values of the?$!?,see?$ERRNO in perlvar.
execl Not implemented.?execl
execle
Not implemented.?execleexec.
execlp Not implemented.?execlpexec.
execv Not implemented.?execvexec.
execve Not implemented.?execveexec.
execvp Not implemented.?execvpexec.
exit This is identical to Perl's builtin?exit()?function for exiting the program,see?exit.
exp This is identical to Perl's builtin?exp()?function for returning the exponent (e-based) of the numerical argument,see?exp.
expm1 Equivalent to?exp(x)?-?1?,but more precise for small argument values [C99].
See also?log1p.
fabs This is identical to Perl's builtin?abs()?function for returning the absolute value of the numerical argument,seeabs.
fclose Not implemented. Use method?IO::Handle::close
fcntl This is identical to Perl's builtin?fcntl()?function,see?fcntl.
fdopen Not implemented. Use method?IO::Handle::new_from_fd
feof
Not implemented. Use method?IO::Handle::eof
ferror
Not implemented. Use method?IO::Handle::error)?instead.
fflush Not implemented. Use method?IO::Handle::flush)?instead. See also?$OUTPUT_AUTOFLUSH in perlvar.
fgetc Not implemented. Use method?IO::Handle::getc
fgetpos
Not implemented. Use method?IO::Seekable::getpos
fgets
Not implemented. Use method?IO::Handle::gets)?instead. Similar to <>,also known as?readline.
fileno Not implemented. Use method?IO::Handle::fileno
floor
This is identical to the C function?floor
fdim
"Positive difference",?x?-?y?if?x?>?y?,zero otherwise [C99].
fegetround Returns the current floating point rounding mode,one of
FE_TONEAREST FE_TOWARDZERO FE_UPWARD FE_UPWARD
FE_TONEAREST?is like?round,0)">FE_TOWARDZERO?is like?trunc?[C99].
fesetround Sets the floating point rounding mode,see?fegetround.
fma "Fused multiply-add",0)">x?*?y + z?,possibly faster (and less lossy) than the explicit two operations [C99].
my $fused = POSIX::fma$y$z;
fmax Maximum of?x?and?y,except when either is?NaN?,returns the other [C99].
$min = POSIX::fmax;
fmin Minimum of?POSIX::fmin;
fmod This is identical to the C function?fmod)?.
$r = ;
It returns the remainder?$r?=?$x?-?$n*$y?,where?$n?=?trunc$x/)?. The?$r?has the same sign as?$x?and magnitude (absolute value) less than the magnitude of?$y?.
fopen Not implemented. Use method?IO::File::openopen.
fork This is identical to Perl's builtin?fork()?function for duplicating the current process,see?fork?and?perlfork?if you are in Windows.
fpathconf Retrieves the value of a configurable limit on a file or directory. This uses file descriptors such as those obtained by calling?POSIX::open?.
The following will determine the maximum length of the longest allowable pathname on the filesystem which holds?/var/foo.
"/var/foo"$path_max = POSIX::fpathconf$fd&POSIX::_PC_PATH_MAXundef?on failure.
fpclassify Returns one of
FP_NORMAL FP_ZERO FP_SUBNORMAL FP_INFINITE FP_NAN
telling the class of the argument [C99].
fprintf Not implemented.?fprintf
fputc
Not implemented.?fputc
fputs
Not implemented.?fputsprint?instead.
fread Not implemented.?fread
free
Not implemented.?free)?is C-specific. Perl does memory management transparently.
freopen Not implemented.?freopen
frexp
Return the mantissa and exponent of a floating-point number.
$mantissa$exponent) = POSIX::frexp( 1.234e56 ;
fscanf Not implemented.?fscanf
fseek
Not implemented. Use method?IO::Seekable::seekseek.
fsetpos Not implemented. Use method?IO::Seekable::setpos
fstat
Get file status. This uses file descriptors such as those obtained by calling?POSIX::open?. The data returned is identical to the data from Perl's builtin?stat?function.
@stats = POSIX::fstat;
fsync Not implemented. Use method?IO::Handle::sync)?instead.
ftell Not implemented. Use method?IO::Seekable::tell
fwrite
Not implemented.?fwriteprint?instead.
getc This is identical to Perl's builtin?getc()?function,see?getc.
getchar Returns one character from STDIN. Identical to Perl's?getc(),102)" rel="nofollow">getc.
getcwd Returns the name of the current working directory. See also?Cwd.
getegid Returns the effective group identifier. Similar to Perl' s builtin variable?$(?,see?$EGID in perlvar.
getenv Returns the value of the specified environment variable. The same information is available through the?%ENVarray.
geteuid Returns the effective user identifier. Identical to Perl's builtin?$>?variable,see?$EUID in perlvar.
getgid Returns the user's real group identifier. Similar to Perl's builtin variable?$)?,see?$GID in perlvar.
getgrgid This is identical to Perl's builtin?getgrgid()?function for returning group entries by group identifiers,seegetgrgid.
getgrnam This is identical to Perl's builtin?getgrnam()?function for returning group entries by group names,seegetgrnam.
getgroups Returns the ids of the user's supplementary groups. Similar to Perl's builtin variable?$GID in perlvar.
getlogin This is identical to Perl's builtin?getlogin()?function for returning the user name associated with the current session,see?getlogin.
getpgrp This is identical to Perl's builtin?getpgrp()?function for returning the process group identifier of the current process,see?getpgrp.
getpid Returns the process identifier. Identical to Perl's builtin variable?$$?,see?$PID in perlvar.
getppid This is identical to Perl's builtin?getppid()?function for returning the process identifier of the parent process of the current process,see?getppid.
getpwnam This is identical to Perl's builtin?getpwnam()?function for returning user entries by user names,see?getpwnam.
getpwuid This is identical to Perl's builtin?getpwuid()?function for returning user entries by user identifiers,see?getpwuid.
gets Returns one line from?STDIN?,similar to <>,also known as the?readline()?function,see?readline.
NOTE: if you have C programs that still use?gets)?function is a source of endless grief because it has no buffer overrun checks. It should?never?be used. The?fgets)?function should be preferred instead.
getuid Returns the user's identifier. Identical to Perl's builtin?$<?variable,see?$UID in perlvar.
gmtime This is identical to Perl's builtin?gmtime()?function for converting seconds since the epoch to a date in Greenwich Mean Time,see?gmtime.
hypot Equivalent to?sqrtx?*?x?+?y * y)?except more stable on very large or very small arguments [C99].
ilogb Integer binary logarithm [C99]
For example?ilogb(20)?is 4,as an integer.
See also?logb.
isalnum Deprecated function whose use raises a warning,and which is slated to be removed in a future Perl version. It is very similar to matching against?qr/ ^ [[:alnum:]]+ $ /x?,which you should convert to use instead. The function is deprecated because 1) it doesn't handle UTF-8 encoded strings properly; and 2) it returns?TRUE?even if the input is the empty string. The function return is always based on the current locale,whereas using locale rules is optional with the regular expression,based on pragmas in effect and pattern modifiers (see?Character set modifiers in perlre?and?Which character set modifier is in effect? in perlre).
The function returns?TRUE?if the input string is empty,or if the corresponding C function returns?TRUE?for every byte in the string.
You may want to use the?/w/?construct instead.
isalpha Deprecated function whose use raises a warning,85)">qr/ ^ [[:alpha:]]+ $ /x?,0)">TRUE?for every byte in the string.
isatty Returns a boolean indicating whether the specified filehandle is connected to a tty. Similar to the?-t?operator,see?-X.
iscntrl Deprecated function whose use raises a warning,85)">qr/ ^ [[:cntrl:]]+ $ /x?,0)">TRUE?for every byte in the string.
isdigit Deprecated function whose use raises a warning,85)">qr/ ^ [[:digit:]]+ $ /x?,221)">/d/?construct instead.
isfinite Returns true if the argument is a finite number (that is,not an infinity,or the not-a-number) [C99].
See also?isinf,?isnan,and?fpclassify.
isgraph Deprecated function whose use raises a warning,85)">qr/ ^ [[:graph:]]+ $ /x?,0)">TRUE?for every byte in the string.
isgreater (Also?isgreaterequal?,0)">isless?,0)">islessequal?,0)">islessgreater?,0)">isunordered?)
Floating point comparisons which handle the?NaN?[C99].
isinf Returns true if the argument is an infinity (positive or negative) [C99].
See also?isfinite,102)" rel="nofollow">fpclassify.
islower Deprecated function whose use raises a warning,85)">qr/ ^ [[:lower:]]+ $ /x?,0)">TRUE?for every byte in the string.
Do?not?use?/[a-z]/?unless you don't care about the current locale.
isnan Returns true if the argument is?NaN?(not-a-number) [C99].
Note that you cannot test for "NaN?-ness" with
$x == $x
since the?NaN?is not equivalent to anything,?including itself.
See also?nan,?fpclassify.
isnormal Returns true if the argument is normal (that is,not a subnormal/denormal,and not an infinity,or a not-a-number) [C99].
See also?fpclassify.
isprint Deprecated function whose use raises a warning,85)">qr/ ^ [[:print:]]+ $ /x?,0)">TRUE?for every byte in the string.
ispunct Deprecated function whose use raises a warning,85)">qr/ ^ [[:punct:]]+ $ /x?,0)">TRUE?for every byte in the string.
isspace Deprecated function whose use raises a warning,85)">qr/ ^ [[:space:]]+ $ /x?,221)">/s/?construct instead.
isupper Deprecated function whose use raises a warning,85)">qr/ ^ [[:upper:]]+ $ /x?,85)">/[A-Z]/?unless you don't care about the current locale.
isxdigit Deprecated function whose use raises a warning,85)">qr/ ^ [[:xdigit:]]+ $ /x?,0)">TRUE?for every byte in the string.
j0
j1
jn
y0
y1
yn The Bessel function of the first kind of the order zero.
kill This is identical to Perl's builtin?kill()?function for sending signals to processes (often to terminate them),seekill.
labs Not implemented. (For returning absolute values of long integers.)?labs
lchown
This is identical to the C function,except the order of arguments is consistent with Perl's builtin?chown()?with the added restriction of only one path,not a list of paths. Does the same thing as the?chown()?function but changes the owner of a symbolic link instead of the file the symbolic link points to.
POSIX::lchown$uid$gid$file_path;
ldexp This is identical to the C function?ldexp)?for multiplying floating point numbers with powers of two.
$x_quadrupled = POSIX::ldexp2;
ldiv Not implemented. (For computing dividends of long integers.)?ldiv/?and?int()?instead.
lgamma The logarithm of the Gamma function [C99].
See also?tgamma.
log1p Equivalent to?log1?+?
log2
Logarithm base two [C99].
See also?expm1.
logb Integer binary logarithm [C99].
For example?logb See also?ilogb.
link This is identical to Perl's builtin?link()?function for creating hard links into files,see?link.
localeconv Get numeric formatting information. Returns a reference to a hash containing the current underlying locale's formatting values. Users of this function should also read?perllocale,which provides a comprehensive discussion of Perl locale handling,including?a section devoted to this function.
Here is how to query the database for the?de?(Deutsch or German) locale.
$loc = POSIX::setlocale&POSIX::LC_ALL"de" "Locale: "$loc"n"$lconv = POSIX::localeconv foreach $property (qw(
decimal_point
thousands_sep
grouping
int_curr_symbol
currency_symbol
mon_decimal_point
mon_thousands_sep
mon_grouping
positive_sign
negative_sign
int_frac_digits
frac_digits
p_cs_precedes
p_sep_by_space
n_cs_precedes
n_sep_by_space
p_sign_posn
n_sign_posn
int_p_cs_precedes
int_p_sep_by_space
int_n_cs_precedes
int_n_sep_by_space
int_p_sign_posn
int_n_sign_posn
))
qq(%s: "%s",n)$property$lconv->{$property}}
The members whose names begin with?int_p_?and?int_n_?were added by POSIX.1-2008 and are only available on systems that support them.
localtime This is identical to Perl's builtin?localtime()?function for converting seconds since the epoch to a date seelocaltime.
log This is identical to Perl's builtin?log()?function,returning the natural (e-based) logarithm of the numerical argument,see?log.
log10 This is identical to the C function?log10
sub log10 { $_[0]) / 10}
or
) / 2.30258509299405 ) * 0.434294481903252 }
longjmp Not implemented.?longjmp)?is C-specific: use?die?instead.
lseek Move the file's read/write position. This uses file descriptors such as those obtained by calling?$off_t = POSIX::lseek0&POSIX::SEEK_SET undef?on failure.
lrint Depending on the current floating point rounding mode,rounds the argument either toward nearest (likeround),toward zero (like?trunc),downward (toward negative infinity),or upward (toward positive infinity) [C99].
For the rounding mode,102)" rel="nofollow">fegetround.
lround Like?
See also?ceil,?floor,?trunc.
malloc Not implemented.?malloc)?is C-specific. Perl does memory management transparently.
mblen This is identical to the C function?mblen)?.
Core Perl does not have any support for the wide and multibyte characters of the C standards,except under UTF-8 locales,so this might be a rather useless function.
However,Perl supports Unicode,see?perluniintro.
mbstowcs This is identical to the C function?mbstowcs)?.
See?mblen.
mbtowc This is identical to the C function?mbtowcmblen.
memchr Not implemented.?memchr
memcmp
Not implemented.?memcmpeq?instead,see?perlop.
memcpy Not implemented.?memcpy=?,102)" rel="nofollow">perlop,or see?substr.
memmove Not implemented.?memmovesubstr.
memset Not implemented.?memsetx?instead,102)" rel="nofollow">perlop.
mkdir This is identical to Perl's builtin?mkdir()?function for creating directories,see?mkdir.
mkfifo This is similar to the C function?mkfifo)?for creating FIFO special files.
if (mkfifo($path,$mode)) { ....
Returns?undef?on failure. The?$mode?is similar to the mode of?mkdir(),102)" rel="nofollow">mkdir,though for?mkfifo?you?mustspecify the?$mode?.
mktime Convert date/time info to a calendar time.
Synopsis:
mktimesecminhourmdaymonyearwday = yday = isdst = -1)
The month (mon?),weekday (wday?),and yearday (yday?) begin at zero,?i.e.,January is 0,not 1; Sunday is 0,not 1; January 1st is 0,not 1. The year (year?) is given in years since 1900;?i.e.,the year 1995 is 95; the year 2001 is 101. Consult your system's?)?manpage for details about these and the other arguments.
Calendar time for December 12,1995,at 10:30 am.
$time_t = POSIX::mktime3010121195 "Date = "POSIX::ctime$time_tundef?on failure.
modf Return the integral and fractional parts of a floating-point number.
$fractional$integralPOSIX::modf3.14 ;
See also?round.
nan Returns not-a-number [C99].
See also?isnan.
nearbyint Returns the nearest integer to the argument,according to the current rounding mode (see?fegetround) [C99].
nextafter Returns the next representable floating point number after?x?in the direction of?$nextafter = POSIX::nextafter;
Like?nexttoward,but potentially less accurate.
nexttoward Returns the next representable floating point number after?$nexttoward = POSIX::nexttoward;
Like?nextafter,but potentially more accurate.
nice This is similar to the C function?nice Returns?undef?on failure.
offsetof Not implemented.?offsetof
open Open a file for reading for writing. This returns file descriptors,not Perl filehandles. Use?POSIX::close
?to close the file.
Open a file read-only with mode 0666.
"foo" ;
Open a file for read and write.
&POSIX::O_RDWR ;
Open a file for write,with truncation.
(
&POSIX::O_WRONLY | &POSIX::O_TRUNC
;
Create a new file with mode 0640. Set up the file for writing.
&POSIX::O_CREAT | &POSIX::O_WRONLY0640
undef?on failure. See also?sysopen.
opendir Open a directory for reading.
$dir = POSIX::opendir"/var" @files = POSIX::readdir$dir POSIX::closedirundef?on failure.
pathconf Retrieves the value of a configurable limit on a file or directory.
The following will determine the maximum length of the longest allowable pathname on the filesystem which holds?/var.
POSIX::pathconf"/var"&POSIX::_PC_PATH_MAX undef?on failure.
pause This is similar to the C function?pause Returns?undef?on failure.
perror This is identical to the C function?perror": "?and the current error string. Use the?warn()?function and the?$!?variable instead,see?warnand?$ERRNO in perlvar.
pipe Create an interprocess channel. This returns file descriptors like those returned by?my $read$writePOSIX::pipePOSIX::write$write"hello"5 POSIX::read$buf;
See also?pipe.
pow Computes?$x?raised to the power?$exponent?.
$ret = POSIX::pow$exponent ;
You can also use the?**?operator,102)" rel="nofollow">perlop.
printf Formats and prints the specified arguments to?STDOUT?. See also?printf.
putc Not implemented.?putcprint?instead.
putchar Not implemented.?putcharprint?instead.
puts Not implemented.?putsprint?instead.
qsort Not implemented.?qsort
raise
Sends the specified signal to the current process. See also?kill?and the?$$?in?$PID in perlvar.
rand Not implemented.?rand()?is non-portable,see?rand?instead.
read Read from a file. This uses file descriptors such as those obtained by calling?POSIX::open?. If the buffer?$buf?is not large enough for the read then Perl will extend it to make room for the request.
$bytes = 3 undef?on failure. See also?sysread.
readdir This is identical to Perl's builtin?readdir()?function for reading directory entries,see?readdir.
realloc Not implemented.?realloc)?is C-specific. Perl does memory management transparently.
remainder Given?x?-?n*n?is the integer closest to?x/y. [C99]
$remainder = POSIX::remainder)
See also?remquo.
remove This is identical to Perl's builtin?unlink()?function for removing files,see?unlink.
remquo Like?remainder?but also returns the low-order bits of the quotient (n) [C99]
(This is quite esoteric interface,mainly used to implement numerical algorithms.)
rename This is identical to Perl's builtin?rename()?function for renaming files,see?rename.
rewind Seeks to the beginning of the file.
rewinddir This is identical to Perl's builtin?rewinddir()?function for rewinding directory entry streams,see?rewinddir.
rint Identical to?lrint.
rmdir This is identical to Perl's builtin?rmdir()?function for removing (empty) directories,see?rmdir.
round Returns the integer (but still as floating point) nearest to the argument [C99].
See also?lround,?modf,and?trunc.
scalbn Returns?x?*?2**y?[C99].
See also?frexp?and?ldexp.
scanf Not implemented.?scanf
setgid
Sets the real group identifier and the effective group identifier for this process. Similar to assigning a value to the Perl's builtin?$)?variable,102)" rel="nofollow">$EGID in perlvar,except that the latter will change only the real user identifier,and that the setgid() uses only a single numeric argument,as opposed to a space-separated list of numbers.
setjmp Not implemented.?eval.
setlocale Modifies and queries the program's underlying locale. Users of this function should read?a section devoted to this function. The discussion here is merely a summary reference for?setlocale)?. Note that Perl itself is almost entirely unaffected by the locale except within the scope of"use locale"?. (Exceptions are listed in?Not within the scope of use locale in perllocale.)
The following examples assume
qw(setlocale LC_ALL LC_CTYPE);
has been issued.
The following will set the traditional UNIX system locale behavior (the second argument?"C"?).
( LC_ALL"C" ;
The following will query the current?LC_CTYPE?category. (No second argument means 'query'.)
LC_CTYPE ;
The following will set the?LC_CTYPE?behaviour according to the locale environment variables (the second argument?""?). Please see your system's?3)?documentation for the locale environment variables' meaning or consult?perllocale.
LC_CTYPE"" LC_COLLATE?behaviour to Argentinian Spanish.?NOTE: The naming and availability of locales depends on your operating system. Please consult?perllocale?for how to find out which locales are available in your system. LC_COLLATE"es_AR.ISO8859-1" ;
setpgid This is similar to the C function?setpgid)?for setting the process group identifier of the current process.
Returns?undef?on failure.
setsid This is identical to the C function?setsid)?for setting the session identifier of the current process.
setuid Sets the real user identifier and the effective user identifier for this process. Similar to assigning a value to the Perl's builtin?$UID in perlvar,except that the latter will change only the real user identifier.
sigaction Detailed signal management. This uses?POSIX::SigAction?objects for the?action?and?oldaction?arguments (the oldaction can also be just a hash reference). Consult your system's?sigaction?manpage for details,see also?POSIX::SigRt?.
Synopsis:
sigactionsignalactionoldaction = 0)
Returns?signal?must be a number (like?SIGHUP?),not a string (like?"SIGHUP"?),though Perl does try hard to understand you.
If you use the?SA_SIGINFO?flag,the signal handler will in addition to the first argument,the signal name,also receive a second argument,a hash reference,inside which are the following keys with the following semantics,as defined by POSIX/SUSv3:
signo the signal number
errno error code if this is zero or lesswas sent by
a user process and uid and pid make senseotherwise by kernel
The following are also defined by POSIX/SUSv3,but unfortunately not very widely implemented:
process id generating signal
uid of status exit value or signal for SIGCHLD
band event for SIGPOLL
A third argument is also passed to the handler,which contains a copy of the raw binary contents of thesiginfo?structure: if a system has some non-POSIX fields,this third argument is where to?unpack()?them from.
Note that not all?siginfo?values make sense simultaneously (some are valid only for certain signals,for example),and not all values make sense from Perl perspective,you should to consult your system's?sigactionand possibly also?siginfo?documentation.
siglongjmp Not implemented.?siglongjmpdie?instead.
signbit Returns zero for positive arguments,non-zero for negative arguments [C99].
sigpending Examine signals that are blocked and pending. This uses?POSIX::SigSet?objects for the?sigset?argument. Consult your system's?sigpending?manpage for details.
Synopsis:
sigpendingsigsetundef?on failure.
sigprocmask Change and/or examine calling process's signal mask. This uses?sigset?andoldsigset?arguments. Consult your system's?sigprocmask?manpage for details.
Synopsis:
sigprocmaskhowsigsetoldsigset = undef?on failure. Note that you can't reliably block or unblock a signal from its own signal handler if you're using safe signals. Other signals can be blocked or unblocked reliably.
sigsetjmp Not implemented.?sigsetjmpeval.
sigsuspend Install a signal mask and suspend process until signal arrives. This uses?POSIX::SigSet?objects for thesignal_mask?argument. Consult your system's?sigsuspend?manpage for details.
Synopsis:
sigsuspendsignal_maskundef?on failure.
sin This is identical to Perl's builtin?sin()?function for returning the sine of the numerical argument,see?sin. See also?Math::Trig.
sinh This is identical to the C function?sinh)?for returning the hyperbolic sine of the numerical argument. See alsoMath::Trig.
sleep This is functionally identical to Perl's builtin?sleep()?function for suspending the execution of the current for process for certain number of seconds,see?sleep. There is one significant difference,however:?POSIX::sleep)returns the number of?unslept?seconds,while the?CORE::sleep)?returns the number of slept seconds.
sprintf This is similar to Perl's builtin?sprintf()?function for returning a string that has the arguments formatted as requested,see?sprintf.
sqrt This is identical to Perl's builtin?sqrt()?function. for returning the square root of the numerical argument,seesqrt.
srand Give a seed the pseudorandom number generator,see?srand.
sscanf Not implemented.?sscanfperlre.
stat This is identical to Perl's builtin?stat()?function for returning information about files and directories.
strcat Not implemented.?strcat.=?instead,102)" rel="nofollow">perlop.
strchr Not implemented.?strchrindex?instead.
strcmp Not implemented.?strcmpeq?or?cmp?instead,102)" rel="nofollow">perlop.
strcoll This is identical to the C function?strcoll)?for collating (comparing) strings transformed using the?strxfrm)function. Not really needed since Perl can do this transparently,see?perllocale.
strcpy Not implemented.?strcpy=?instead,102)" rel="nofollow">perlop.
strcspn Not implemented.?strcspnperlre.
strerror Returns the error string for the specified errno. Identical to the string form of?$ERRNO in perlvar.
strftime Convert date and time information to string. Returns the string.
Synopsis:
strftimefmt-1year?) is given in years since 1900,0)">)?manpage for details about these and the other arguments. If you want your code to be portable,your format (fmt?) argument should use only the conversion specifiers defined by the ANSI C standard (C89,to play safe). These are?aAbBcdHIjmMpSUwWxXyYZ%?. But even then,theresults?of some of the conversion specifiers are non-portable. For example,the specifiers?aAbBcpZ?change according to the locale settings of the user,and both how to set locales (the locale names) and what output to expect are non-standard. The specifier?c?changes according to the timezone settings of the user and the timezone computation rules of the operating system. The?Z?specifier is notoriously unportable since the names of timezones are non-standard. Sticking to the numeric specifiers is the safest route.
The given arguments are made consistent as though by calling?)?before calling your system's)?function,except that the?isdst?value is not affected.
The string for Tuesday,December 12,1995.
$str = POSIX::strftime"%A,%B %d,%Y" 952 "$strn";
strlen Not implemented.?strlenlength()?instead,see?length.
strncat Not implemented.?strncatperlop.
strncmp Not implemented.?strncmpperlop.
strncpy Not implemented.?strncpyperlop.
strpbrk Not implemented.?strpbrkperlre.
strrchr Not implemented.?strrchr
strspn
Not implemented.?strspnperlre.
strstr This is identical to Perl's builtin?index()?function,102)" rel="nofollow">index.
strtod String to double translation. Returns the parsed number and the number of characters in the unparsed portion of the string. Truly POSIX-compliant systems set?$!?($ERRNO?) to indicate a translation error,so clear?$!?before calling?strtod?. However,non-POSIX systems may not check for overflow,and therefore will never set?$!?.
strtod?respects any POSIX?)?LC_TIME?settings,regardless of whether or not it is called from Perl code that is within the scope of?locale?.
To parse a string?$str?as a floating point number use
$! = 0$num$n_unparsedPOSIX::strtod$str;
The second returned item and?$!?can be used to check for valid input:
if $str eq '') || $n_unparsed != ) || $! die "Non-numeric input $str" . $! ? ": $!n" : "n"}
When called in a scalar context?strtod?returns the parsed number.
strtok Not implemented.?strtokperlre,or?split.
strtol String to (long) integer translation. Returns the parsed number and the number of characters in the unparsed portion of the string. Truly POSIX-compliant systems set?strtol?. However,0)">strtol?should respect any POSIX?setlocale()?settings.
To parse a string?$str?as a number in some base?$base?use
POSIX::strtol$str$base;
The base should be zero or between 2 and 36,inclusive. When the base is zero or omitted?strtol?will use the string itself to determine the base: a leading "0x" or "0X" means hexadecimal; a leading "0" means octal; any other leading characters mean decimal. Thus,"1234" is parsed as a decimal number,"01234" as an octal number,and "0x1234" as a hexadecimal number.
The second returned item and?) || !"Non-numeric input $str" . "n"strtol?returns the parsed number.
strtold Like?strtod?but for long doubles. Defined only if the system supports long doubles.
strtoul String to unsigned (long) integer translation.?strtoul)?is identical to?strtol)?except that?)?only parses unsigned integers. See?strtol?for details.
Note: Some vendors supply?strtod)?and?)?but not?)?. Other vendors that do supply)?parse "-1" as a valid value.
strxfrm String transformation. Returns the transformed string.
$dst = POSIX::strxfrm$src ;
Used in conjunction with the? Not really needed since Perl can do this transparently,102)" rel="nofollow">perllocale.
sysconf Retrieves values of system configurable variables.
The following will get the machine's clock speed.
$clock_ticks = POSIX::sysconf&POSIX::_SC_CLK_TCK undef?on failure.
system This is identical to Perl's builtin?system()?function,see?system.
tan This is identical to the C function?tan
tanh
This is identical to the C function?tanh
tcdrain
This is similar to the C function?tcdrain)?for draining the output queue of its argument stream.
Returns?undef?on failure.
tcflow This is similar to the C function?tcflow)?for controlling the flow of its argument stream.
Returns?undef?on failure.
tcflush This is similar to the C function?tcflush)?for flushing the I/O buffers of its argument stream.
Returns?undef?on failure.
tcgetpgrp This is identical to the C function?tcgetpgrp)?for returning the process group identifier of the foreground process group of the controlling terminal.
tcsendbreak This is similar to the C function?tcsendbreak)?for sending a break on its argument stream.
Returns?undef?on failure.
tcsetpgrp This is similar to the C function?tcsetpgrp)?for setting the process group identifier of the foreground process group of the controlling terminal.
Returns?undef?on failure.
tgamma The Gamma function [C99].
See also?lgamma.
time This is identical to Perl's builtin?time()?function for returning the number of seconds since the epoch (whatever it is for the system),see?time.
times The?times()?function returns elapsed realtime since some point in the past (such as system startup),user and system times for this process,and user and system times used by child processes. All times are returned in clock ticks.
$realtime$user$system$cuser$csystem = POSIX::times;
Note: Perl's builtin?times()?function returns four values,measured in seconds.
tmpfile Not implemented. Use method?IO::File::new_tmpfile
tmpnam
Returns a name for a temporary file.
$tmpfile = POSIX::tmpnam;
For security reasons,which are probably detailed in your system's documentation for the C library?tmpnam)function,this interface should not be used; instead see?File::Temp.
tolower This is identical to the C function,except that it can apply to a single character or to a whole string,and currently operates as if the locale always is "C". Consider using the?lc()?function,see?lc,or the equivalent?L?operator inside doublequotish strings.
toupper This is similar to the C function,221)">uc()?function,see?uc,0)">U?operator inside doublequotish strings.
trunc Returns the integer toward zero from the argument [C99].
See also?round.
ttyname This is identical to the C function?ttyname)?for returning the name of the current terminal.
tzname Retrieves the time conversion information from the?tzname?variable.
POSIX::tzset$std$dstPOSIX::tzname;
tzset This is identical to the C function?tzset)?for setting the current timezone based on the environment variableTZ?,to be used by?localtime(),0)">)?functions.
umask This is identical to Perl's builtin?umask()?function for setting (and querying) the file creation permission mask,see?umask.
uname Get name of current operating system.
$sysname$nodename$release$version$machinePOSIX::uname;
Note that the actual meanings of the various fields are not that well standardized,do not expect any great portability. The?$sysname?might be the name of the operating system,the?$nodename?might be the name of the host,139)">$release?might be the (major) release number of the operating system,139)">$version?might be the (minor) release number of the operating system,and the?$machine?might be a hardware identifier. Maybe.
ungetc Not implemented. Use method?IO::Handle::ungetc)?instead.
unlink This is identical to Perl's builtin?unlink.
utime This is identical to Perl's builtin?utime()?function for changing the time stamps of files and directories,seeutime.
vfprintf Not implemented.?vfprintfprintf?instead.
vprintf Not implemented.?vprintfprintf?instead.
vsprintf Not implemented.?vsprintfsprintf?instead.
wait This is identical to Perl's builtin?wait()?function,see?wait.
waitpid Wait for a child process to change state. This is identical to Perl's builtin?waitpid()?function,see?waitpid.
$pid = POSIX::waitpidPOSIX::WNOHANG "status = "$? / 256);
wcstombs This is identical to the C function?wcstombsmblen.
wctomb This is identical to the C function?wctombmblen.
write Write to a file. This uses file descriptors such as those obtained by calling?&POSIX::O_WRONLY $buf = "hello"undef?on failure.
See also?syswrite.
CLASSES
POSIX::SigAction
-
new Creates a new?POSIX::SigAction?object which corresponds to the C?struct?sigaction?. This object will be destroyed automatically when it is no longer needed. The first parameter is the handler,a sub reference. The second parameter is a?POSIX::SigSet?object,it defaults to the empty set. The third parameter contains thesa_flags?,it defaults to 0.
$sigset = POSIX::SigSet->newSIGINTSIGQUIT$sigaction = POSIX::SigAction &handler$sigset&POSIX::SA_NOCLDSTOP
- ;
This?POSIX::SigAction?object is intended for use with the?POSIX::sigaction)?function.
-
handler
-
mask
-
flags accessor functions to get/set the values of a SigAction object.
$sigset = $sigaction->mask->flags&POSIX::SA_RESTART;
-
safe accessor function for the "safe signals" flag of a SigAction object; see?perlipc?for general information on safe (a.k.a. "deferred") signals. If you wish to handle a signal safely,use this accessor to set the "safe" flag in thePOSIX::SigAction?object:
->safe1;
You may also examine the "safe" flag on the output action object which is filled in when given as the third parameter to?)?:
$new_action$old_action$old_action# previous SIGINT handler used safe signals
}
POSIX::SigRt
-
%SIGRT A hash of the POSIX realtime signal handlers. It is an extension of the standard?%SIG?,the$POSIX::SIGRT{SIGRTMIN}?is roughly equivalent to?$SIG{SIGRTMIN}?,but the right POSIX moves (see below) are made with the?POSIX::SigSet?and?POSIX::sigaction?instead of accessing the?%SIG?.
You can set the?%POSIX::SIGRT?elements to set the POSIX realtime signal handlers,221)">delete?and?existson the elements,and use?scalar?on the?%POSIX::SIGRT?to find out how many POSIX realtime signals there are available?SIGRTMAX?-?SIGRTMIN?+?SIGRTMAX?is a valid POSIX realtime signal).
Setting the?%SIGRT?elements is equivalent to calling this:
sub new $rtsig$handler$flags@_POSIX::SigSet$rtsig$sigact = $sigact}
The flags default to zero,if you want something different you can either use?local?on$POSIX::SigRt::SIGACTION_FLAGS?,or you can derive from POSIX::SigRt and define your own?new)?(the tied hash STORE method of the?%SIGRT?calls?$SIGACTION_FLAGS$rtsigranges from zero to?1)?.
Just as with any signal,you can use?$oa)?to retrieve the installed signal handler (or,rather,the signal action).
NOTE:?whether POSIX realtime signals really work in your system,or whether Perl has been compiled so that it works with them,is outside of this discussion.
-
SIGRTMIN Return the minimum POSIX realtime signal number available,or?undef?if no POSIX realtime signals are available.
-
SIGRTMAX Return the maximum POSIX realtime signal number available,102); font-weight:bold" rel="nofollow">undef?if no POSIX realtime signals are available.
POSIX::SigSet
new Create a new SigSet object. This object will be destroyed automatically when it is no longer needed. Arguments may be supplied to initialize the set.
Create an empty set.
->new;
Create a set with?SIGUSR1?.
&POSIX::SIGUSR1 ;
addset Add a signal to a SigSet object.
$sigset->addset&POSIX::SIGUSR2 undef?on failure.
delset Remove a signal from the SigSet object.
->delsetundef?on failure.
emptyset Initialize the SigSet object to be empty.
->emptysetundef?on failure.
fillset Initialize the SigSet object to include all signals.
->fillsetundef?on failure.
ismember Tests the SigSet object to see if it contains a specific signal.
->ismember"contains SIGUSR1n"}
POSIX::Termios
new Create a new Termios object. This object will be destroyed automatically when it is no longer needed. A Termios object corresponds to the?termios?C struct.?)?mallocs a new one,139)">getattr)?fills it from a file descriptor,139)">setattr)?sets a file descriptor's parameters to match Termios' contents.
$termios = POSIX::Termios;
getattr Get terminal control attributes.
Obtain the attributes for?stdin?.
$termios->getattr( 0 ) # Recommended for clarity.
$termios->getattr()
Obtain the attributes for stdout.
$termios->getattr1 undef?on failure.
getcc Retrieve a value from the?c_cc?field of a?termios?object. The?c_cc?field is an array so an index must be specified.
$c_cc[1] = ->getcc;
getcflag Retrieve the?c_cflag?field of a?termios?object.
$c_cflag = ->getcflag;
getiflag Retrieve the?c_iflag?field of a?$c_iflag = ->getiflag;
getispeed Retrieve the input baud rate.
$ispeed = ->getispeed;
getlflag Retrieve the?c_lflag?field of a?$c_lflag = ->getlflag;
getoflag Retrieve the?c_oflag?field of a?$c_oflag = ->getoflag;
getospeed Retrieve the output baud rate.
$ospeed = ->getospeed;
setattr Set terminal control attributes.
Set attributes immediately for stdout.
->setattr1&POSIX::TCSANOW undef?on failure.
setcc Set a value in the?->setcc&POSIX::VEOF;
setcflag Set the?->setcflag$c_cflag | &POSIX::CLOCAL ;
setiflag Set the?->setiflag$c_iflag | &POSIX::BRKINT ;
setispeed Set the input baud rate.
->setispeed&POSIX::B9600 undef?on failure.
setlflag Set the?->setlflag$c_lflag | &POSIX::ECHO ;
setoflag Set the?->setoflag$c_oflag | &POSIX::OPOST ;
setospeed Set the output baud rate.
->setospeedundef?on failure.
Baud rate values B38400?B75?B200?B134?B300?B1800?B150?B0?B19200?B1200?B9600?B600?B4800?B50?B2400?B110
Terminal interface values TCSADRAIN?TCSANOW?TCOON?TCIOFLUSH?TCOFLUSH?TCION?TCIFLUSH?TCSAFLUSH?TCIOFF?TCOOFF
c_cc?field values VEOF?VEOL?VERASE?VINTR?VKILL?VQUIT?VSUSP?VSTART?VSTOP?VMIN?VTIME?NCCS
c_cflag?field values CLOCAL?CREAD?CSIZE?CS5?CS6?CS7?CS8?CSTOPB?HUPCL?PARENB?PARODD
c_iflag?field values BRKINT?ICRNL?IGNBRK?IGNCR?IGNPAR?INLCR?INPCK?ISTRIP?IXOFF?IXON?PARMRK
c_lflag?field values ECHO?ECHOE?ECHOK?ECHONL?ICANON?IEXTEN?ISIG?NOFLSH?TOSTOP
c_oflag?field values OPOST
PATHNAME CONSTANTS
POSIX CONSTANTS
_POSIX_ARG_MAX?_POSIX_CHILD_MAX?_POSIX_CHOWN_RESTRICTED?_POSIX_JOB_CONTROL?_POSIX_LINK_MAX_POSIX_MAX_CANON?_POSIX_MAX_INPUT?_POSIX_NAME_MAX?_POSIX_NGROUPS_MAX?_POSIX_NO_TRUNC?_POSIX_OPEN_MAX_POSIX_PATH_MAX?_POSIX_PIPE_BUF?_POSIX_SAVED_IDS?_POSIX_SSIZE_MAX?_POSIX_STREAM_MAX_POSIX_TZNAME_MAX?_POSIX_VDISABLE?_POSIX_VERSION
SYSTEM CONFIGURATION
_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
ERRNO
E2BIG?EACCES?EADDRINUSE?EADDRNOTAVAIL?EAFNOSUPPORT?EAGAIN?EALREADY?EBADF?EBADMSG?EBUSY?ECANCELEDECHILD?ECONNABORTED?ECONNREFUSED?ECONNRESET?EDEADLK?EDESTADDRREQ?EDOM?EDQUOT?EEXIST?EFAULT?EFBIGEHOSTDOWN?EHOSTUNREACH?EIDRM?EILSEQ?EINPROGRESS?EINTR?EINVAL?EIO?EISCONN?EISDIR?ELOOP?EMFILE?EMLINKEMSGSIZE?ENAMETOOLONG?ENETDOWN?ENETRESET?ENETUNREACH?ENFILE?ENOBUFS?ENODATA?ENODEV?ENOENT?ENOEXECENOLCK?ENOLINK?ENOMEM?ENOMSG?ENOPROTOOPT?ENOSPC?ENOSR?ENOSTR?ENOSYS?ENOTBLK?ENOTCONN?ENOTDIRENOTEMPTY?ENOTRECOVERABLE?ENOTSOCK?ENOTSUP?ENOTTY?ENXIO?EOPNOTSUPP?EOTHER?EOVERFLOW?EOWNERDEAD?EPERMEPFNOSUPPORT?EPIPE?EPROCLIM?EPROTO?EPROTONOSUPPORT?EPROTOTYPE?ERANGE?EREMOTE?ERESTART?EROFS?ESHUTDOWNESOCKTNOSUPPORT?ESPIPE?ESRCH?ESTALE?ETIME?ETIMEDOUT?ETOOMANYREFS?ETXTBSY?EUSERS?EWOULDBLOCK?EXDEV
FCNTL
FD_CLOEXEC?F_DUPFD?F_GETFD?F_GETFL?F_GETLK?F_OK?F_RDLCK?F_SETFD?F_SETFL?F_SETLK?F_SETLKW?F_UNLCKF_WRLCK?O_ACCMODE?O_APPEND?O_CREAT?O_EXCL?O_NOCTTY?O_NONBLOCK?O_RDONLY?O_RDWR?O_TRUNC?O_WRONLY
FLOAT
DBL_DIG?DBL_EPSILON?DBL_MANT_DIG?DBL_MAX?DBL_MAX_10_EXP?DBL_MAX_EXP?DBL_MIN?DBL_MIN_10_EXPDBL_MIN_EXP?FLT_DIG?FLT_EPSILON?FLT_MANT_DIG?FLT_MAX?FLT_MAX_10_EXP?FLT_MAX_EXP?FLT_MINFLT_MIN_10_EXP?FLT_MIN_EXP?FLT_RADIX?FLT_ROUNDS?LDBL_DIG?LDBL_EPSILON?LDBL_MANT_DIG?LDBL_MAXLDBL_MAX_10_EXP?LDBL_MAX_EXP?LDBL_MIN?LDBL_MIN_10_EXP?LDBL_MIN_EXP
FLOATING-POINT ENVIRONMENT
FE_DOWNWARD?FE_TONEAREST?FE_TOWARDZERO?FE_UPWARD?on systems that support them.
LIMITS
ARG_MAX?CHAR_BIT?CHAR_MAX?CHAR_MIN?CHILD_MAX?INT_MAX?INT_MIN?LINK_MAX?LONG_MAX?LONG_MIN?MAX_CANONMAX_INPUT?MB_LEN_MAX?NAME_MAX?NGROUPS_MAX?OPEN_MAX?PATH_MAX?PIPE_BUF?SCHAR_MAX?SCHAR_MIN?SHRT_MAXSHRT_MIN?SSIZE_MAX?STREAM_MAX?TZNAME_MAX?UCHAR_MAX?UINT_MAX?ULONG_MAX?USHRT_MAX
LOCALE
LC_ALL?LC_COLLATE?LC_CTYPE?LC_MONETARY?LC_NUMERIC?LC_TIME?LC_MESSAGES?on systems that support them.
MATH
HUGE_VAL FP_ILOGB0?FP_ILOGBNAN?FP_INFINITE?FP_NAN?FP_NORMAL?FP_SUBNORMAL?FP_ZERO?INFINITY?NAN?Inf?NaN?M_1_PIM_2_PI?M_2_SQRTPI?M_E?M_LN10?M_LN2?M_LOG10E?M_LOG2E?M_PI?M_PI_2?M_PI_4?M_SQRT1_2?M_SQRT2?on systems with C99 support.
SIGNAL
SA_NOCLDSTOP?SA_NOCLDWAIT?SA_NODEFER?SA_ONSTACK?SA_RESETHAND?SA_RESTART?SA_SIGINFO?SIGABRT?SIGALRMSIGCHLD?SIGCONT?SIGFPE?SIGHUP?SIGILL?SIGINT?SIGKILL?SIGPIPE?SIGQUIT?SIGSEGV?SIGSTOP?SIGTERM?SIGTSTPSIGTTIN?SIGTTOU?SIGUSR1?SIGUSR2?SIG_BLOCK?SIG_DFL?SIG_ERR?SIG_IGN?SIG_SETMASK?SIG_UNBLOCK
STAT
STDLIB
EXIT_FAILURE?EXIT_SUCCESS?MB_CUR_MAX?RAND_MAX
STDIO
BUFSIZ?EOF?FILENAME_MAX?L_ctermid?L_cuserid?L_tmpname?TMP_MAX
TIME
UNISTD
R_OK?SEEK_CUR?SEEK_END?SEEK_SET?STDIN_FILENO?STDOUT_FILENO?STDERR_FILENO?W_OK?X_OK
WAIT
