我可以像这样调用我的程序：

1. ./main solved.txt
2. cat unsolved.txt | ./main
3. cat unsolved.txt | ./main solved.txt

我正在使用它来知道是否需要从C行POSIX标准中读取管道中的数据：

#include <iostream>
#include <sstream>
#include <stdio.h>
#include <unistd.h>

int main( int argumentsCount,char* argumentsStringList[] )
{
    std::stringstream inputedPipeLineString;

    if( argumentsCount > 1 )
    {
        printf( "argumentsStringList[1]: %s",argumentsStringList[ 1 ] );
    }

    // If it is passed input through the terminal pipe line,get it.
    if( !isatty( fileno( stdin ) ) )
    {
        // Converts the std::fstream "std::cin" to std::stringstream which natively
        // supports conversion to string.
        inputedPipeLineString << std::cin.rdbuf();

        printf( "inputedPipeLineString: %s",inputedPipeLineString.str().c_str() );
    }
}

但是现在我想使用C11标准,而我所爱的fileno和isatty也是这样的.那么在C 11上有一个替代方案呢？

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问题是当使用-std = C 11编译时,在stdio.h / cstdlib上,fileno和isatty是未定义的,因为它们是POSIX的东西.所以,一个解决方案是使用-std = GNU 11而不是-std = C 11.但是可以使用-std = C 11编写别的东西来编译吗？