在perl脚本中执行命令时，perl可以响应命令中提出的STDOUT请求吗？

Question

I'm executing a command inside a perl script and when that command completes, a question is sent to STDOUT requesting a Y or N answer to a question. If no answer is given (ie I just end the script) then we have a hung process in the shell waiting for an answer. How can I supply the desired Y answer?

perl v5.8.4 solaris 10

Answer 1

• Simplest :

  Use shell's ability to redirect "Y" into command's STDIN:

   `echo "Y" | your_command_expecting_Y`; 

  or (slightly worse but more flexible).

   `your_command_expecting_Y < /my/file/containing/one/line/with_Y_in_it.txt`; 

• More complicated but infinitely more flexible and Perl native:

  Use Expect module

   use Expect; # create an Expect object by spawning another process my $exp = Expect->spawn($command, @params); $exp->send("Y\\n"); 

Answer 2

期望

Answer 3

Assuming you always want to answer 'Y' and the command will only prompt once :

system("echo Y | your_command_here");

If the command will prompt more than once and you always want to answer 'Y':

system("yes Y | your_command_here");

Otherwise, Expect is probably your best bet as the others have suggestes.