#23 should rdbuf()->status() match exit() value?

[Trevor Hickey]

I wrote a custom program in C++ that looks liket this:

#include <cstdlib>
int main(){exit(1);}

It works in my shell, as I expect:

$ ./main
$ echo $?
1
$

However, the pstream library gices me -1

redi::pstream proc("./main");
auto return_code = proc.rdbuf()->status();
std::cout << return_code << '\n'; //prints -1

If I close the process, it gives me 36096

redi::pstream proc("./main");
proc.close();
auto return_code = proc.rdbuf()->status();
std::cout << return_code << '\n'; //prints 36096

If I read all the process streams, it gives me back 256:

redi::pstream proc("./main",redi::pstreams::psterr|redi::pstreams::pstdout);
while(std::Getline(proc.err(),temp)){}
proc.clear();
while(std::Getline(proc.out(),temp)){}
proc.close();
auto return_code = proc.rdbuf()->status();
std::cout << return_code << '\n'; //prints 256

Am I doing something wrong? Is a return value from 0 - 255 guaranteed to match the status()?

[Trevor Hickey]

like*

getline*

gives*

I can't edit the ticket.

[Trevor Hickey]

Returns: The exit status of the child process, or -1 if wait() has not yet been called to wait for the child to exit.

Ignore the -1 then

[Trevor Hickey]

Am I suppose to use WEXITSTATUS on wait()?

[Trevor Hickey]

I figured it out. I have to call WEXITSTATUS() on the value returned back from status();

[Trevor Hickey]

/close

[Jonathan Wakely]

Right, it returns the same value as wait or waitpid so you need to use WIFEXITED, WEXITSTATUS etc.