posix_isatty
(PHP 4, PHP 5)
posix_isatty — Determine if a file descriptor is an interactive terminal
Описание
bool posix_isatty
( int $fd
)
Determines if the file descriptor fd refers to a valid terminal type device.
Список параметров
- fd
-
The file descriptor.
Возвращаемые значения
Returns TRUE if fd is an open descriptor connected to a terminal and FALSE otherwise.
- PHP Руководство
- Функции по категориям
- Индекс функций
- Справочник функций
- Расширения для управления процессами программ
- POSIX
- posix_access
- posix_ctermid
- posix_errno
- posix_get_last_error
- posix_getcwd
- posix_getegid
- posix_geteuid
- posix_getgid
- posix_getgrgid
- posix_getgrnam
- posix_getgroups
- posix_getlogin
- posix_getpgid
- posix_getpgrp
- posix_getpid
- posix_getppid
- posix_getpwnam
- posix_getpwuid
- posix_getrlimit
- posix_getsid
- posix_getuid
- posix_initgroups
- posix_isatty
- posix_kill
- posix_mkfifo
- posix_mknod
- posix_setegid
- posix_seteuid
- posix_setgid
- posix_setpgid
- posix_setrlimit
- posix_setsid
- posix_setuid
- posix_strerror
- posix_times
- posix_ttyname
- posix_uname
Коментарии
Can be useful to determine whether output is being piped elsewhere, for PHP shell scripts, for example;
#!/usr/local/bin/php
<?php
if ( !posix_isatty(STDOUT) ) {
fwrite(STDOUT, "Invalid TTY\n");
exit(2);
}
fwrite(STDOUT, "Enter you name\n");
$name = fgets(STDIN);
fwrite(STDOUT,"Hello $name\n");
exit(0);
?>
If this script is like:
script.php > outfile
outfile will contain "Invalid TTY"
It's quite complicated to understand its movements. But it determines if the file_descriptor is open AND connected to a terminal.
Thus, while receiving data from the STDIN, for example, it will return false.
This move is useful to optionally pipe STDIN to a PHP script, to avoid hanging when nothing is from STDIN.
<?php
// Simply echoes the contents from STDIN if any
// and "no stdin" if not.
echo (posix_isatty(STDIN)) ? 'no stdin' . PHP_EOL : file_get_contents('php://stdin');
?>