@@ -585,6 +585,42 @@ static void *Task_Ready;
585585 //SetEvent(Task_Ready);
586586}
587587
588+ //Helper function for OS_Create_Process:
589+ //see: https://stackoverflow.com/questions/41976446/pipe2-vs-pipe-fcntl-why-different
590+ static inline REBOOL Open_Pipe_Fails (int pipefd [2 ]) {
591+ #ifdef USE_OLD_PIPE
592+ //
593+ // NOTE: pipe() is POSIX, but pipe2() is Linux-specific. With pipe() it
594+ // takes an additional call to fcntl() to request non-blocking behavior,
595+ // so it's a small amount more work. However, there are other flags which
596+ // if aren't passed atomically at the moment of opening allow for a race
597+ // condition in threading if split, e.g. FD_CLOEXEC.
598+ //
599+ // (If you don't have FD_CLOEXEC set on the file descriptor, then all
600+ // instances of CALL will act as a /WAIT.)
601+ //
602+ // At time of writing, this is mostly academic...but the code needed to be
603+ // patched to work with pipe() since some older libcs do not have pipe2().
604+ // So the ability to target both are kept around, saving the pipe2() call
605+ // for later Linuxes known to have it (and O_CLOEXEC).
606+ //
607+ if (pipe (pipefd ) < 0 )
608+ return TRUE;
609+ int direction ; // READ=0, WRITE=1
610+ for (direction = 0 ; direction < 2 ; ++ direction ) {
611+ int oldflags = fcntl (pipefd [direction ], F_GETFD );
612+ if (oldflags < 0 )
613+ return TRUE;
614+ if (fcntl (pipefd [direction ], F_SETFD , oldflags | FD_CLOEXEC ) < 0 )
615+ return TRUE;
616+ }
617+ #else
618+ if (pipe2 (pipefd , O_CLOEXEC ))
619+ return TRUE;
620+ #endif
621+ return FALSE;
622+ }
623+
588624
589625/***********************************************************************
590626**
@@ -641,26 +677,23 @@ static void *Task_Ready;
641677 if (flags & FLAG_SHELL ) flag_shell = TRUE;
642678 if (flags & FLAG_INFO ) flag_info = TRUE;
643679
644- if (input_type == STRING_TYPE
645- || input_type == BINARY_TYPE ) {
646- if (pipe2 (stdin_pipe , O_CLOEXEC | O_NONBLOCK ) < 0 ) {
680+ if (input_type == STRING_TYPE || input_type == BINARY_TYPE ) {
681+ if (Open_Pipe_Fails (stdin_pipe )) {
647682 goto stdin_pipe_err ;
648683 }
649684 }
650- if (output_type == STRING_TYPE
651- || output_type == BINARY_TYPE ) {
652- if (pipe2 (stdout_pipe , O_CLOEXEC | O_NONBLOCK ) < 0 ) {
685+ if (output_type == STRING_TYPE || output_type == BINARY_TYPE ) {
686+ if (Open_Pipe_Fails (stdout_pipe )) {
653687 goto stdout_pipe_err ;
654688 }
655689 }
656- if (err_type == STRING_TYPE
657- || err_type == BINARY_TYPE ) {
658- if (pipe2 (stderr_pipe , O_CLOEXEC | O_NONBLOCK ) < 0 ) {
690+ if (err_type == STRING_TYPE || err_type == BINARY_TYPE ) {
691+ if (Open_Pipe_Fails (stderr_pipe )) {
659692 goto stderr_pipe_err ;
660693 }
661694 }
662695
663- if (pipe2 (info_pipe , O_CLOEXEC | O_NONBLOCK ) < 0 ) {
696+ if (Open_Pipe_Fails (info_pipe ) ) {
664697 goto info_pipe_err ;
665698 }
666699
@@ -760,7 +793,9 @@ static void *Task_Ready;
760793 sh = getenv ("SHELL" );
761794 if (sh == NULL ) {
762795 int err = 2 ; /* shell does not exist */
763- write (info_pipe [W ], & err , sizeof (err ));
796+ if (write (info_pipe [W ], & err , sizeof (err )) == -1 ) {
797+ //nothing there... just to avoid "unused-result" compiler warning
798+ }
764799 exit (EXIT_FAILURE );
765800 }
766801 argv_new = OS_Make ((argc + 3 ) * sizeof (char * ));
@@ -773,7 +808,9 @@ static void *Task_Ready;
773808 execvp (argv [0 ], argv );
774809 }
775810child_error :
776- write (info_pipe [W ], & errno , sizeof (errno ));
811+ if (write (info_pipe [W ], & errno , sizeof (errno )) == -1 ) {
812+ //nothing there... just to avoid "unused-result" compiler warning
813+ }
777814 exit (EXIT_FAILURE ); /* get here only when exec fails */
778815 } else if (fpid > 0 ) {
779816 /* parent */
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