"connection reset by peer"的可能原因
对方没有close就cancel了socket pair，你就会收到一个sig_pipe信号然后strerror会显示“connection reset by peer”的错误。防止程序退出解决方法就是处理SIGPIPE信号
屏蔽信号的代码
void InstalSignal(){ signal(SIGHUP ,SIG_IGN ); /* hangup, generated when terminal disconnects */ signal(SIGINT ,SIG_IGN ); /* interrupt, generated from terminal special char */ signal(SIGQUIT ,SIG_IGN ); /* (*) quit, generated from terminal special char */ signal(SIGILL ,SIG_IGN ); /* (*) illegal instruction (not reset when caught)*/ signal(SIGTRAP ,SIG_IGN ); /* (*) trace trap (not reset when caught) */ signal(SIGABRT ,SIG_IGN ); /* (*) abort process */ #ifdef D_AIX signal(SIGEMT ,SIG_IGN ); /* EMT intruction */ #endif signal(SIGFPE ,SIG_IGN ); /* (*) floating point exception */ signal(SIGKILL ,SIG_IGN ); /* kill (cannot be caught or ignored) */ signal(SIGBUS ,SIG_IGN ); /* (*) bus error (specification exception) */ signal(SIGSEGV ,SIG_IGN ); /* (*) segmentation violation */ signal(SIGSYS ,SIG_IGN ); /* (*) bad argument to system call */ signal(SIGPIPE ,SIG_IGN ); /* write on a pipe with no one to read it */ signal(SIGALRM ,SIG_IGN ); /* alarm clock timeout */ //signal(SIGTERM ,stopproc ); /* software termination signal */ signal(SIGURG ,SIG_IGN ); /* (+) urgent contition on I/O channel */ signal(SIGSTOP ,SIG_IGN ); /* (@) stop (cannot be caught or ignored) */ signal(SIGTSTP ,SIG_IGN ); /* (@) interactive stop */ signal(SIGCONT ,SIG_IGN ); /* (!) continue (cannot be caught or ignored) */ signal(SIGCHLD ,SIG_IGN); /* (+) sent to parent on child stop or exit */ signal(SIGTTIN ,SIG_IGN); /* (@) background read attempted from control terminal*/ signal(SIGTTOU ,SIG_IGN); /* (@) background write attempted to control terminal */ signal(SIGIO ,SIG_IGN); /* (+) I/O possible, or completed */ signal(SIGXCPU ,SIG_IGN); /* cpu time limit exceeded (see setrlimit()) */ signal(SIGXFSZ ,SIG_IGN); /* file size limit exceeded (see setrlimit()) */ #ifdef D_AIX signal(SIGMSG ,SIG_IGN); /* input data is in the ring buffer */ #endif signal(SIGWINCH,SIG_IGN); /* (+) window size changed */ signal(SIGPWR ,SIG_IGN); /* (+) power-fail restart */ //signal(SIGUSR1 ,stopproc); /* user defined signal 1 */ //signal(SIGUSR2 ,stopproc); /* user defined signal 2 */ signal(SIGPROF ,SIG_IGN); /* profiling time alarm (see setitimer) */ #ifdef D_AIX signal(SIGDANGER,SIG_IGN); /* system crash imminent; free up some page space */ #endif signal(SIGVTALRM,SIG_IGN); /* virtual time alarm (see setitimer) */ #ifdef D_AIX signal(SIGMIGRATE,SIG_IGN); /* migrate process */ signal(SIGPRE ,SIG_IGN); /* programming exception */ signal(SIGVIRT ,SIG_IGN); /* AIX virtual time alarm */ signal(SIGALRM1,SIG_IGN); /* m:n condition variables - RESERVED - DON 'T USE */ signal(SIGWAITING,SIG_IGN); /* m:n scheduling - RESERVED - DON 'T USE */ signal(SIGCPUFAIL ,SIG_IGN); /* Predictive De-configuration of Processors - */ signal(SIGKAP,SIG_IGN); /* keep alive poll from native keyboard */ signal(SIGRETRACT,SIG_IGN); /* monitor mode should be relinguished */ signal(SIGSOUND ,SIG_IGN); /* sound control has completed */ signal(SIGSAK ,SIG_IGN); /* secure attention key */ #endif}