我试图找出是否安装了命令行程序,以便以后可以使用。
到目前为止,我所尝试的是:
int whichReturn = system("command -v THE_CL_PROGRAM >/dev/null && { exit 50; }|| { exit 60; }");
if (whichReturn == 12800) { //system 'apparently' returns the return value *256 (50*256 = 12800)
//...
}
然而,它似乎总是返回60,因此失败。
有更简单的方法吗?或者有人可以指出我的错误在哪里?
由于
答案 0 :(得分:1)
使用which
的完整程序:
isthere.cpp:
#include <iostream>
#include <cstdlib>
#include <sstream>
int main(int argc, char* argv[])
{
std::ostringstream cmd;
cmd << "which " << argv[1] << " >/dev/null 2>&1";
bool isInstalled = (system(cmd.str().c_str()) == 0);
std::cout << argv[1] << " is "<< ((isInstalled)?"":"NOT ") << "installed! << std::endl;
}
输出:
$ ./isthere ls
ls is installed!
$ ./isthere grep
grep is installed!
$ ./isthere foo
foo is NOT installed!