picosat.c build error

[ThePrez]

picosat.c has #include <sys/unistd.h> but on some systems it should just be #include <unistd.h>

The build error on IBM i is manifested as:

    In file included from pycosat.c:19:0:
    picosat.c:8150:24: fatal error: sys/unistd.h: No such file or directory
     #include <sys/unistd.h>
                            ^

To solve my immediate concern, one could simply #ifdef __PASE__ (defined on IBM i), but I am opening an issue rather than a PR so the project owners can choose their preferred way to address.

Thanks!

[github-actions]

Hi there, thank you for your contribution!

This issue has been automatically marked as stale because it has not had recent activity. It will be closed automatically if no further activity occurs.

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Thanks!

[dholth]

I was able to include just unistd.h on osx

#include <unistd.h>

int main(int argc, char **argv) {
    return 0;
}