confstr--Linux下获取C标准库信息的函数

Linux下获取C标准库信息的函数  confstr

man 3 confstr

NAME

       confstr - get configuration dependent string variables

SYNOPSIS

       #include <unistd.h>

       size_t confstr(int name, char *buf, size_t len);

函数根据name的值来获取相关信息，name目前支持的值有

1 _CS_GNU_LIBC_VERSION  表示查询GNU C库版本 只在GNU C库的2.3.2开始支持

      _CS_GNU_LIBC_VERSION (GNU C library only; since glibc 2.3.2)

              A string which identifies the GNU C library version on this system (e.g, "glibc 2.3.4").

2 CS_GNU_LIBPTHREAD_VERSION  查询posix标准的实现方

       _CS_GNU_LIBPTHREAD_VERSION (GNU C library only; since glibc 2.3.2)

              A string which identifies the POSIX implementation supplied by this C library (e.g, "NPTL 2.3.4" or "linuxthreads-0.10").

3   _CS_PATH   PATH环境变量的值

     _CS_PATH

              A value for the PATH variable which indicates where all the POSIX.2 standard utilities can be found.