可能是为了将他们分开,所以没用32,33。。至于为什么中间要空出2个值,而不是1或者3或者4……,,这个得问当初这样的设计的人了:你问什么只空出2个值呢??。
------解决方案-------------------- 纠正一下,32和33也是可靠信号 Linux supports 32 real-time signals, numbered from 32 (SIGRTMIN) to 63 (SIGRTMAX). (Programs should always refer to real-time signals using notation SIGRTMIN+n, since the range of real-time signal numbers varies across Unices.)(英文摘自man手册)