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instance method

IO#pid

ios.pid → integer

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

    GetOpenFile(io, fptr);
    if (!fptr->pid)
        return Qnil;
    return PIDT2NUM(fptr->pid);
}

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

Example

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

See also #pathconf #pos #oflush #pos= also in 4.1 · 4.0 · 3.4 · 3.3 · 3.2 · 3.1

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