readline

(PHP 4, PHP 5, PHP 7, PHP 8)

readlineLiest eine Zeile

Beschreibung

readline(?string $prompt = null): string|false

Liest eine einzelne Zeile vom Benutzer ein. Sie müssen diese Zeile selbst mittels readline_add_history() zur History hinzufügen.

Parameter-Liste

prompt

Sie können eine Zeichenkette angeben, mit dem Sie den Benutzer zur Eingabe auffordern.

Rückgabewerte

Gibt eine einzelne Zeile des Benutzers zurück. Der Zeile, die zurückgegeben wird, fehlt das abschließende Zeichen für einen Zeilenvorschub. Können keine weiteren Daten gelesen werden, wird false zurückgegeben.

Beispiele

Beispiel #1 readline()-Beispiel

<?php
// Drei Kommandos vom Benutzer abfragen
for ($i=0; $i < 3; $i++) {
$line = readline("Command: ");
readline_add_history($line);
}

// History ausgeben
print_r(readline_list_history());

// Variablen ausgeben
print_r(readline_info());
?>

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User Contributed Notes 13 notes

up
4
Antony Penn
4 years ago
Christian's code works well, but if you want to be able to hide the user input and not echo it to screen, you need to add -s to the read command. The code below is an expanded function that allows an optional prompt and optional hiding of the input:

function read_password($prompt=null, $hide=false)
{
    if($prompt) print $prompt;
    $s = ($hide) ? '-s' : '';
    $f=popen("read $s; echo \$REPLY","r");
    $input=fgets($f,100);
    pclose($f);
    if($hide) print "\n";
    return $input;
}
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4
turdsurfer
7 years ago
If your CLI script accepts input from STDIN and you also want it to prompt for a password (e.g. as mysql client does), then readline() won't work for you.
What you need to do is read from the terminal device as shown below.

function readline_terminal($prompt = '') {
    $prompt && print $prompt;
    $terminal_device = '/dev/tty';
    $h = fopen($terminal_device, 'r');
    if ($h === false) {
        #throw new RuntimeException("Failed to open terminal device $terminal_device");
        return false; # probably not running in a terminal.
    }
    $line = rtrim(fgets($h),"\r\n");
    fclose($h);
    return $line;
}
$pass = readline_terminal('Password: ');
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4
rojaro at gmail dot com
15 years ago
Note that readline() will return boolean "false" when the user presses CTRL+D.
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2
taneli at crasman dot fi
14 years ago
If you want to prefill the prompt with something when using readline, this worked for me:

<?php
 
function readline_callback($ret)
  {
    global
$prompt_answer, $prompt_finished;
   
$prompt_answer = $ret;
   
$prompt_finished = TRUE;
   
readline_callback_handler_remove();
  }

 
readline_callback_handler_install('Enter some text> ',
                                   
'readline_callback');

 
$prefill = 'foobar';
  for (
$i = 0; $i < strlen($prefill); $i++)
  {
   
readline_info('pending_input', substr($prefill, $i, 1));
   
readline_callback_read_char();
  }

 
$prompt_finished = FALSE;
 
$prompt_answer = FALSE;
  while (!
$prompt_finished)
   
readline_callback_read_char();
  echo
'You wrote: ' . $prompt_answer . "\n";
?>
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3
Anonymous
12 years ago
The readline library is not available on Windows.

<?php
if (PHP_OS == 'WINNT') {
  echo
'$ ';
 
$line = stream_get_line(STDIN, 1024, PHP_EOL);
} else {
 
$line = readline('$ ');
}
?>
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1
cox at idecnet dot com
22 years ago
In CGI mode be sure to call:

ob_implicit_flush(true);

at the top of your script if you want to be able to output data before and after the prompt.

-- Tomas V.V.Cox
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1
soletan at toxa dot de
17 years ago
To haukew at gmail dot com:

readline provides more features than reading a single line of input ... your example misses line editing and history. If you don't need that, use something as simple as this:

function readline( $prompt = '' )
{
    echo $prompt;
    return rtrim( fgets( STDIN ), "\n" );
}
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0
christian at gaeking dot de
20 years ago
A workaround if readline is not compiled into php, because for example the command is only needed within an installation routine. It works as follows under Linux:

$f=popen("read; echo \$REPLY","r");
$input=fgets($f,100);
pclose($f);       
echo "Entered: $input\n";
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-1
thflori
5 years ago
If you want to block remove previous text and wonder that an empty string does not work: the workaround is to use an space with cursor left:

<?php

echo "> ";
readline(" \e[D");

?>
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-2
sean
14 years ago
I wanted a function that would timeout if readline was waiting too long... this works on php CLI on linux:

<?php

function readline_timeout($sec, $def)
{
    return
trim(shell_exec('bash -c ' .
       
escapeshellarg('phprlto=' .
           
escapeshellarg($def) . ';' .
           
'read -t ' . ((int)$sec) . ' phprlto;' .
           
'echo "$phprlto"')));
}

?>

Just call readline_timeout(5, 'whatever') to either read something from stdin, or timeout in 5 seconds and default to 'whatever'.  I tried just using shell_exec without relying on bash -c, but that didn't work for me, so I had to go the round about way.
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-2
Anonymous
6 years ago
a few observations....

I use Cygwin PHP v7 and readline is available. The readline_list_history() function though is not defined.

A prompt with escape sequences are sanitized, so use something like:

<?php
   
echo("\e[0m\e[34mPromt>\e[0m");
   
$inp = readline(' ');
?>

I have not fully documented it, but I see that sometimes strings beginning with punctuation characters do not make it into the history with readline_add_history(). They also sometimes clear the prompt string.
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-3
Ixios
5 years ago
Works under windows, and under php 7.2.0 :

$arr = [];

for ($i=0; $i < 3; $i++) {
        $arr[$i] = readline("Commande : ");
}

// Output
print_r($arr);

----------

Output:

Commande : 658
Commande : 965
Commande : 478
Array
(
    [0] => 658
    [1] => 965
    [2] => 478
)
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-5
roddric dot kasen at gmail dot com
8 years ago
<?php

class ConsoleQuestion
{

    function
readline()
    {
        return
rtrim(fgets(STDIN));
    }
}

//Example1
$line = new ConsoleQuestion();
$prompt = "What Is Your Name: ";
echo
$prompt;
$answer = $line->readline();
echo
"You Entered: " . $answer;

//Example2 (comment Ex1 then uncomment Ex2)
/*$prompt = "What Is Your Name: ";
echo $prompt;
$answer =  "You Entered: " . rtrim( fgets( STDIN ));
echo $answer;*/

?>
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