printf中的格式控制符 %m

一同事突然问到的问题：

      printf("watchdog fork(): %m\n");

 

之前也没见过， 在网上搜了下， 原来%m是strerror(errno)的替代， 原文如下：

 

 

GNU glibc provides an extension to printf, %m, which outputs
strerror(errno). It's a bit superfluous in my opinion, but some
projects make heavy use of it. Would newlib accept a patch to add this
feature?

Cheers,
Shaun

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