从/ dev / tty读取时，PHP（cli）吞下一个字节

Question

I am having an issue with PHP (cli) when using /dev/tty as the file. The actual scenario is slightly more complex and is not mentioned here to keep the question simple.

To run PHP code from STDIN, I am able to run the command as follows,

$ php
<?php
echo "hello world\n";
?>
<CTRL-D>
hello world
$

However, when run through /dev/tty , the following happens,

$ php /dev/tty
<?php
echo "hello world\n";
?>
<CTRL-D>
?php
echo "hello world\n";
?>
$

NOTE: The first character < is simply lost and php processes the input as plain text. We can simplify the test to the following,

Working

$ php
abcd
abcd
$

Not Working

$ php /dev/tty
abcd
bcd
$

I have run strace to check if php reads the input correctly and it seems to be so, as shown below,

$ strace -o /tmp/1 php /dev/tty ; grep "bcd" /tmp/1
abcd
<CTRL-D>
bcd
read(4, "abcd\n", 4096)                 = 5
write(1, "bcd\n", 4)                    = 4
$

This seems pretty simple and, I feel, I am missing something very basic here.

Does anyone know why PHP (cli) behaves this way when reading from /dev/tty ?

Additional Info:-

• PHP Versions: 5.3.3 (cli) and 5.5.20 (cli)
• OS: Linux (CentOS 6.4 and Fedora 19)

Answer 1

php /dev/tty \\<?php echo "hi\\n"; ?> hi

Escaping the < worked. I don't know why though :D Probably related to the fact that this is in ran in bash.