c - execvpe 的可移植替代品

Question

execvpe 函数是一个 GNU 扩展。如果我希望我的代码可移植到非 gnu libc，如何将 execvpe 调用更改为可移植？

execvp 不会设置新程序的环境，并且 execle poth 不允许传递数组作为参数，并且不会尝试解析来自 PATH 的可执行文件。

Answer 1

直接更改环境。

每the POSIX exec() documentation (加粗我的):

... In addition, the following variable, which must be declared by the user if it is to be used directly:

extern char **environ;

is initialized as a pointer to an array of character pointers to the environment strings. The argv and environ arrays are each terminated by a null pointer. The null pointer terminating the argv array is not counted in argc.

Applications can change the entire environment in a single operation by assigning the environ variable to point to an array of character pointers to the new environment strings. ...

所以而不是

exec...e( ...., myNewEnv );

你可以做到

extern char **environ;

   .
   .
   .

environ = myNewEnv;
exec...(...);