=item acos
This is identical to the C function C<acos()>, returning
-the arcus cosine of its numerical argument.
+the arcus cosine of its numerical argument. See also L<Math::Trig>.
=item alarm
=item asin
This is identical to the C function C<asin()>, returning
-the arcus sine of its numerical argument.
+the arcus sine of its numerical argument. See also L<Math::Trig>.
=item assert
=item atan
This is identical to the C function C<atan()>, returning the
-arcus tangent of its numerical argument.
+arcus tangent of its numerical argument. See also L<Math::Trig>.
=item atan2
This is identical to Perl's builtin C<atan2()> function, returning
the arcus tangent defined by its two numerical arguments, the I<y>
-coordinate and the I<x> coordinate.
+coordinate and the I<x> coordinate. See also L<Math::Trig>.
=item atexit
This is identical to Perl's builtin C<cos()> function, for returning
the cosine of its numerical argument, see L<perlfunc/cos>.
+See also L<Math::Trig>.
=item cosh
This is identical to the C function C<cosh()>, for returning
-the hyperbolic cosine of its numeric argument.
+the hyperbolic cosine of its numeric argument. See also L<Math::Trig>.
=item creat
=item ctime
-This is identical to the C function C<ctime()>.
+This is identical to the C function C<ctime()> and equivalent
+to C<asctime(localtime(...))>, see L</asctime> and L</localtime>.
=item cuserid
-Get the character login name of the user.
+Get the login name of the owner of the current process.
$name = POSIX::cuserid();
=item difftime
-This is identical to the C function C<difftime()>.
+This is identical to the C function C<difftime()>, for returning
+the time difference (in seconds) between two times (as returned
+by C<time()>), see L</time>.
=item div
=item dup
-This is similar to the C function C<dup()>.
+This is similar to the C function C<dup()>, for duplicating a file
+descriptor.
This uses file descriptors such as those obtained by calling
C<POSIX::open>.
=item dup2
-This is similar to the C function C<dup2()>.
+This is similar to the C function C<dup2()>, for duplicating a file
+descriptor to an another known file descriptor.
This uses file descriptors such as those obtained by calling
C<POSIX::open>.
$errno = POSIX::errno();
-This identical to the numerical values of the C<$!>, see L<perlvar>.
+This identical to the numerical values of the C<$!>, see L<perlvar/$ERRNO>.
=item execl
=item fclose
-Use method C<IO::Handle::close()> instead.
+Use method C<IO::Handle::close()> instead, or see L<perlfunc/close>.
=item fcntl
=item fdopen
-Use method C<IO::Handle::new_from_fd()> instead.
+Use method C<IO::Handle::new_from_fd()> instead, or see L<perlfunc/open>.
=item feof
-Use method C<IO::Handle::eof()> instead.
+Use method C<IO::Handle::eof()> instead, or see L<perlfunc/eof>.
=item ferror
=item fflush
Use method C<IO::Handle::flush()> instead.
+See also L<perlvar/$OUTPUT_AUTOFLUSH>.
=item fgetc
-Use method C<IO::Handle::getc()> instead.
+Use method C<IO::Handle::getc()> instead, or see L<perlfunc/read>.
=item fgetpos
-Use method C<IO::Seekable::getpos()> instead.
+Use method C<IO::Seekable::getpos()> instead, or see L<L/seek>.
=item fgets
-Use method C<IO::Handle::gets()> instead. Similar to <>, also known
+Use method C<IO::Handle::gets()> instead. Similar to E<lt>E<gt>, also known
as L<perlfunc/readline>.
=item fileno
-Use method C<IO::Handle::fileno()> instead.
+Use method C<IO::Handle::fileno()> instead, or see L<perlfunc/fileno>.
=item floor
=item fopen
-Use method C<IO::File::open()> instead.
+Use method C<IO::File::open()> instead, or see L<perlfunc/open>.
=item fork
-This is identical to Perl's builtin C<fork()> function.
+This is identical to Perl's builtin C<fork()> function
+for duplicating the current process, see L<perlfunc/fork>
+and L<perlfork> if you are in Windows.
=item fpathconf
Return the mantissa and exponent of a floating-point number.
- ($mantissa, $exponent) = POSIX::frexp( 3.14 );
+ ($mantissa, $exponent) = POSIX::frexp( 1.234e56 );
=item fscanf
-fscanf() is C-specific--use <> and regular expressions instead.
+fscanf() is C-specific, use E<lt>E<gt> and regular expressions instead.
=item fseek
-Use method C<IO::Seekable::seek()> instead.
+Use method C<IO::Seekable::seek()> instead, or see L<perlfunc/seek>.
=item fsetpos
-Use method C<IO::Seekable::setpos()> instead.
+Use method C<IO::Seekable::setpos()> instead, or seek L<perlfunc/seek>.
=item fstat
=item ftell
-Use method C<IO::Seekable::tell()> instead.
+Use method C<IO::Seekable::tell()> instead, or see L<perlfunc/tell>.
=item fwrite
=item getchar
-Returns one character from STDIN.
+Returns one character from STDIN. Identical to Perl's C<getc()>,
+see L<perlfunc/getc>.
=item getcwd
Returns the name of the current working directory.
+See also L<Cwd>.
=item getegid
-Returns the effective group id.
+Returns the effective group identifier. Similar to Perl' s builtin
+variable C<$(>, see L<perlvar/$EGID>.
=item getenv
=item geteuid
-Returns the effective user id.
+Returns the effective user identifier. Identical to Perl's builtin C<$E<gt>>
+variable, see L<perlvar/$EUID>.
=item getgid
-Returns the user's real group id.
+Returns the user's real group identifier. Similar to Perl's builtin
+variable C<$)>, see L<perlvar/$GID>.
=item getgrgid
-This is identical to Perl's builtin C<getgrgid()> function,
-see L<perlfunc/getgrgid>.
+This is identical to Perl's builtin C<getgrgid()> function for
+returning group entries by group identifiers, see
+L<perlfunc/getgrgid>.
=item getgrnam
-This is identical to Perl's builtin C<getgrnam()> function,
-see L<perlfunc/getgrnam>.
+This is identical to Perl's builtin C<getgrnam()> function for
+returning group entries by group names, see L<perlfunc/getgrnam>.
=item getgroups
-Returns the ids of the user's supplementary groups.
+Returns the ids of the user's supplementary groups. Similar to Perl's
+builtin variable C<$)>, see L<perlvar/$GID>.
=item getlogin
-This is identical to Perl's builtin C<getlogin()> function,
-see L<perlfunc/getlogin>.
+This is identical to Perl's builtin C<getlogin()> function for
+returning the user name associated with the current session, see
+L<perlfunc/getlogin>.
=item getpgrp
-This is identical to Perl's builtin C<getpgrp()> function,
-see L<perlfunc/getpgrp>.
+This is identical to Perl's builtin C<getpgrp()> function for
+returning the prcess group identifier of the current process, see
+L<perlfunc/getpgrp>.
=item getpid
-Returns the process's id.
+Returns the process identifier. Identical to Perl's builtin
+variable C<$$>, see L<perlvar/$PID>.
=item getppid
-This is identical to Perl's builtin C<getppid()> function,
-see L<perlfunc/getppid>.
+This is identical to Perl's builtin C<getppid()> function for
+returning the process identifier of the parent process of the current
+process , see L<perlfunc/getppid>.
=item getpwnam
-This is identical to Perl's builtin C<getpwnam()> function,
-see L<perlfunc/getpwnam>.
+This is identical to Perl's builtin C<getpwnam()> function for
+returning user entries by user names, see L<perlfunc/getpwnam>.
=item getpwuid
-This is identical to Perl's builtin C<getpwuid()> function,
-see L<perlfunc/getpwuid>.
+This is identical to Perl's builtin C<getpwuid()> function for
+returning user entries by user identifiers, see L<perlfunc/getpwuid>.
=item gets
-Returns one line from C<STDIN>, similar to <>, also known
-as the C<readline()> functions, see L<perlfunc/readline>.
+Returns one line from C<STDIN>, similar to E<lt>E<gt>, also known
+as the C<readline()> function, see L<perlfunc/readline>.
+
+B<NOTE>: if you have C programs that still use C<gets()>, be very
+afraid. The C<gets()> function is a source of endless grief because
+it has no buffer overrun checks. It should B<never> be used. The
+C<fgets()> function should be preferred instead.
=item getuid
-Returns the user's id.
+Returns the user's identifier. Identical to Perl's builtin C<$E<lt>> variable,
+see L<perlvar/$UID>.
=item gmtime
-This is identical to Perl's builtin C<gmtime()> function,
+This is identical to Perl's builtin C<gmtime()> function for
+converting seconds since the epoch to a date in Greenwich Mean Time,
see L<perlfunc/gmtime>.
=item isalnum
This is identical to the C function, except that it can apply to a single
character or to a whole string. Consider using regular expressions and the
-C</[[:isalnum:]]/> construct instead.
+C</[[:alnum:]]/> construct instead, or possibly the C</\w/> construct.
=item isalpha
This is identical to the C function, except that it can apply to a single
character or to a whole string. Consider using regular expressions and the
-C</[[:isalpha:]]/> construct instead.
+C</[[:alpha:]]/> construct instead.
=item isatty
This is identical to the C function, except that it can apply to a single
character or to a whole string. Consider using regular expressions and the
-C</[[:iscntrl:]]/> construct instead.
+C</[[:cntrl:]]/> construct instead.
=item isdigit
This is identical to the C function, except that it can apply to a single
character or to a whole string. Consider using regular expressions and the
-C</[[:isdigit:]]/> construct instead.
+C</[[:digit:]]/> construct instead, or the C</\d/> construct.
=item isgraph
This is identical to the C function, except that it can apply to a single
character or to a whole string. Consider using regular expressions and the
-C</[[:isgraph:]]/> construct instead.
+C</[[:graph:]]/> construct instead.
=item islower
This is identical to the C function, except that it can apply to a single
character or to a whole string. Consider using regular expressions and the
-C</[[:islower:]]/> construct instead.
+C</[[:lower:]]/> construct instead. Do B<not> use C</[a-z]/>.
=item isprint
This is identical to the C function, except that it can apply to a single
character or to a whole string. Consider using regular expressions and the
-C</[[:isprint:]]/> construct instead.
+C</[[:print:]]/> construct instead.
=item ispunct
This is identical to the C function, except that it can apply to a single
character or to a whole string. Consider using regular expressions and the
-C</[[:ispunct:]]/> construct instead.
+C</[[:punct:]]/> construct instead.
=item isspace
This is identical to the C function, except that it can apply to a single
character or to a whole string. Consider using regular expressions and the
-C</[[:isspace:]]/> construct instead.
+C</[[:space:]]/> construct instead, or the C</\s/> construct.
+(Note that C</\s/> and C</[[:space:]]/> are slightly different in that
+C</[[:space:]]/> can normally match a vertical tab, while C</\s/> does
+not.)
=item isupper
This is identical to the C function, except that it can apply to a single
character or to a whole string. Consider using regular expressions and the
-C</[[:isupper:]]/> construct instead.
+C</[[:upper:]]/> construct instead. Do B<not> use C</[A-Z]/>.
=item isxdigit
This is identical to the C function, except that it can apply to a single
character or to a whole string. Consider using regular expressions and the
-C</[[:isxdigit:]]/> construct instead.
+C</[[:xdigit:]]/> construct instead, or simply C</[0-9a-f]/i>.
=item kill
-This is identical to Perl's builtin C<kill()> function.
+This is identical to Perl's builtin C<kill()> function for sending
+signals to processes (often to terminate them), see L<perlfunc/kill>.
=item labs
+(For returning absolute values of long integers.)
labs() is C-specific, see L<perlfunc/abs> instead.
=item ldexp
-This is identical to the C function C<ldexp()>.
+This is identical to the C function C<ldexp()>
+for multiplying floating point numbers with powers of two.
+
+ $x_quadrupled = POSIX::ldexp($x, 2);
=item ldiv
+(For computing dividends of long integers.)
ldiv() is C-specific, use C</> and C<int()> instead.
=item link
-This is identical to Perl's builtin C<link()> function.
+This is identical to Perl's builtin C<link()> function
+for creating hard links into files, see L<perlfunc/link>.
=item localeconv
=item localtime
-This is identical to Perl's builtin C<localtime()> function.
+This is identical to Perl's builtin C<localtime()> function for
+converting seconds since the epoch to a date see L<perlfunc/localtime>.
=item log
=item mblen
This is identical to the C function C<mblen()>.
+Perl does not have any support for the wide and multibyte
+characters of the C standards, so this might be a rather
+useless function.
=item mbstowcs
This is identical to the C function C<mbstowcs()>.
+Perl does not have any support for the wide and multibyte
+characters of the C standards, so this might be a rather
+useless function.
=item mbtowc
This is identical to the C function C<mbtowc()>.
+Perl does not have any support for the wide and multibyte
+characters of the C standards, so this might be a rather
+useless function.
=item memchr
This is identical to the C function C<perror()>, which outputs to the
standard error stream the specified message followed by ": " and the
current error string. Use the C<warn()> function and the C<$!>
-variable instead, see L<perlfunc/warn> and L<perlvar>.
+variable instead, see L<perlfunc/warn> and L<perlvar/$ERRNO>.
=item pipe
=item raise
Sends the specified signal to the current process.
-See also L<perlfunc/kill> and the C<$$> in L<perlvar>.
+See also L<perlfunc/kill> and the C<$$> in L<perlvar/$PID>.
=item rand
-rand() is non-portable, see L<perlfunc/rand> instead.
+C<rand()> is non-portable, see L<perlfunc/rand> instead.
=item read
=item scanf
-scanf() is C-specific--use <> and regular expressions instead,
+scanf() is C-specific, use E<lt>E<gt> and regular expressions instead,
see L<perlre>.
=item setgid
-Sets the real group id for this process.
+Sets the real group identifier and the effective group identifier for
+this process. Similar to assigning a value to the Perl's builtin
+C<$)> variable, see L<perlvar/$GID>, except that the latter
+will change only the real user identifier, and that the setgid()
+uses only a single numeric argument, as opposed to a space-separated
+list of numbers.
=item setjmp
=item setpgid
-This is similar to the C function C<setpgid()>.
+This is similar to the C function C<setpgid()> for
+setting the process group identifier of the current process.
Returns C<undef> on failure.
=item setsid
-This is identical to the C function C<setsid()>.
+This is identical to the C function C<setsid()> for
+setting the session identifier of the current process.
=item setuid
-Sets the real user id for this process.
+Sets the real user identifier and the effective user identifier for
+this process. Similar to assigning a value to the Perl's builtin
+C<$E<lt>> variable, see L<perlvar/$UID>, except that the latter
+will change only the real user identifier.
=item sigaction
This is identical to Perl's builtin C<sin()> function
for returning the sine of the numerical argument,
-see L<perlfunc/sin>.
+see L<perlfunc/sin>. See also L<Math::Trig>.
=item sinh
This is identical to the C function C<sinh()>
for returning the hyperbolic sine of the numerical argument.
+See also L<Math::Trig>.
=item sleep
=item stat
-This is identical to Perl's builtin C<stat()> function.
+This is identical to Perl's builtin C<stat()> function
+for retutning information about files and directories.
=item strcat
=item strcmp
-strcmp() is C-specific, use C<eq> instead, see L<perlop>.
+strcmp() is C-specific, use C<eq> or C<cmp> instead, see L<perlop>.
=item strcoll
=item strcspn
-strcspn() is C-specific, use regular expressions instead.
+strcspn() is C-specific, use regular expressions instead,
+see L<perlre>.
=item strerror
Returns the error string for the specified errno.
-Identical to the string form of the C<$!>, see L<perlvar>.
+Identical to the string form of the C<$!>, see L<perlvar/$ERRNO>.
=item strftime
=item strpbrk
-strpbrk() is C-specific, use regular expressions instead, see L<perlre>.
+strpbrk() is C-specific, use regular expressions instead,
+see L<perlre>.
=item strrchr
=item tan
This is identical to the C function C<tan()>, returning the
-tangent of the numerical argument.
+tangent of the numerical argument. See also L<Math::Trig>.
=item tanh
This is identical to the C function C<tanh()>, returning the
-hyperbolic tangent of the numerical argument.
+hyperbolic tangent of the numerical argument. See also L<Math::Trig>.
=item tcdrain
=item tcgetpgrp
This is identical to the C function C<tcgetpgrp()> for returning the
-process group id of the foreground process group of the controlling
+process group identifier of the foreground process group of the controlling
terminal.
=item tcsendbreak
=item tcsetpgrp
This is similar to the C function C<tcsetpgrp()> for setting the
-process group id of the foreground process group of the controlling
+process group identifier of the foreground process group of the controlling
terminal.
Returns C<undef> on failure.
=item tmpfile
-Use method C<IO::File::new_tmpfile()> instead.
+Use method C<IO::File::new_tmpfile()> instead, or see L<File::Temp>.
=item tmpnam
$tmpfile = POSIX::tmpnam();
-See also the L<File::Temp> module.
+For security reasons, which are probably detailed in your system's
+documentation for the C library tmpnam() function, this interface
+should not be used; instead see L<File::Temp>.
=item tolower
Get name of current operating system.
- ($sysname, $nodename, $release, $version, $machine ) = POSIX::uname();
+ ($sysname, $nodename, $release, $version, $machine) = POSIX::uname();
+
+Note that the actual meanings of the various fields are not
+that well standardized, do not expect any great portability.
+The C<$sysname> might be the name of the operating system,
+the C<$nodename> might be the name of the host, the C<$release>
+might be the (major) release number of the operating system,
+the C<$version> might be the (minor) release number of the
+operating system, and the C<$machine> might be a hardware identifier.
+Maybe.
=item ungetc
Wait for a child process to change state. This is identical to Perl's
builtin C<waitpid()> function, see L<perlfunc/waitpid>.
- $pid = POSIX::waitpid( -1, &POSIX::WNOHANG );
+ $pid = POSIX::waitpid( -1, POSIX::WNOHANG );
print "status = ", ($? / 256), "\n";
=item wcstombs
This is identical to the C function C<wcstombs()>.
+Perl does not have any support for the wide and multibyte
+characters of the C standards, so this might be a rather
+useless function.
=item wctomb
This is identical to the C function C<wctomb()>.
+Perl does not have any support for the wide and multibyte
+characters of the C standards, so this might be a rather
+useless function.
=item write
=back
-=head1 CREATION
-
-This document generated by ./mkposixman.PL version 19960129.
-
projects / p5sagit/p5-mst-13.2.git / blobdiff