头文件中SIGUNUSED的确切位置在哪里？

我有一些必须针对多个平台进行编译的代码.下面将使代码编译,但是我想知道SIGUNUSED符号的实际定义位置：

工作守则

#ifdef LINUX
#define SIGEMT SIGUNUSED
#endif

…

void set_sig_trap()
{
   signal( SIGHUP, Signal );       /* floating point exception            */
   signal( SIGINT , Signal );      /* Interrupt                           */
   signal( SIGQUIT, Signal );      /* quit                                */
   signal( SIGILL, Signal );       /* Illegal instruction                 */
   signal( SIGTRAP, Signal );      /* trace trap                          */
   signal( SIGABRT, Signal );      /* Process abort signal                */
   signal( SIGEMT, Signal );       /* EMT instruction                     */
   signal( SIGFPE, Signal );       /* Floating point exception            */
   signal( SIGBUS, Signal );       /* bus error                           */
   signal( SIGSEGV, Signal );      /* Segmentation violation              */
   signal( SIGSYS, Signal );       /* bad argument to system call         */
   signal( SIGPIPE, Signal );      /* write on a pipe - no one to read it */
   signal( SIGTERM, Signal );      /* Software termination sig. from kill */
   signal( SIGALRM, Signal );      /* alarm clock                         */
   return;
}

…

我在/usr/include中寻找SIGUNUSED,没有任何点击.它不在signal.h中.它来自哪里？

更新：

我不认为信号定义会在signal.h之外,因为响应表明递归搜索确实找到了定义：

me@mymachine.:/usr/include $grep -d recurse SIGUNUSED *
asm/signal.h:#define    SIGUNUSED       31
asm-arm/signal.h:#define        SIGUNUSED       31
asm-ia64/signal.h:/* signal 31 is no longer "unused", but the SIGUNUSED macro remains for backwards compatibility */
asm-ia64/signal.h:#define       SIGUNUSED       31
asm-parisc/signal.h:#define     SIGUNUSED       31
asm-parisc/signal.h:#define SIGRESERVE  SIGUNUSED
asm-powerpc/signal.h:#define    SIGUNUSED       31
asm-s390/signal.h:#define SIGUNUSED       31
asm-x86/signal.h:#define        SIGUNUSED       31
bits/signum.h:#define SIGUNUSED 31

谢谢！

解决方法:

我看到它在bits / signum.h中定义,其中包含在signal.h中：

#define SIGUNUSED 31

也许您忘记了递归grep？

标签：c-3,linux,signals
来源： https://codeday.me/bug/20191209/2095635.html