Provided by: linux-doc-2.6.15_2.6.15-23.39_all bug

NAME

       test_and_set_bit - Set a bit and return its old value

SYNOPSIS

       int test_and_set_bit  (int nr, volatile unsigned long * addr);

ARGUMENTS

       nr     Bit to set

       addr   Address to count from

DESCRIPTION

       This  operation  is atomic and cannot be reordered. It may be reordered
       on other architectures than x86. It also implies a memory barrier.