method

pid

v1_8_6_287 - Show latest stable - Class: IO

pid()

public

Returns the process ID of a child process associated with ios. This will be set by IO::popen.

   pipe = IO.popen("-")
   if pipe
     $stderr.puts "In parent, child pid is #{pipe.pid}"
   else
     $stderr.puts "In child, pid is #{$$}"
   end

produces:

   In child, pid is 26209
   In parent, child pid is 26209

/*
 *  call-seq:
 *     ios.pid    => fixnum
 *  
 *  Returns the process ID of a child process associated with
 *  <em>ios</em>. This will be set by <code>IO::popen</code>.
 *     
 *     pipe = IO.popen("-")
 *     if pipe
 *       $stderr.puts "In parent, child pid is #{pipe.pid}"
 *     else
 *       $stderr.puts "In child, pid is #{$$}"
 *     end
 *     
 *  <em>produces:</em>
 *     
 *     In child, pid is 26209
 *     In parent, child pid is 26209
 */

static VALUE
rb_io_pid(io)
    VALUE io;
{
    OpenFile *fptr;

    GetOpenFile(io, fptr);
    if (!fptr->pid)
        return Qnil;
    return INT2FIX(fptr->pid);
}

pid

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