proc getAppFilename(): string {....raises: [], tags: [ReadIOEffect], forbids: [].}

proc getcwd(): string {....raises: [], tags: [], forbids: [].}

proc signal(signum: cint; handler: SighandlerT): SighandlerT {.importc,
    header: "<signal.h>", ...raises: [], tags: [], forbids: [].}

proc system(cmd: cstring): cint {.importc, header: "<stdlib.h>", ...raises: [],
                                  tags: [], forbids: [].}