Merge pull request #9966 from richardkchapman/pipe-run-check

HPCC-17591 All calls to IPipeProcess::run should check the return value

Reviewed-by: Gavin Halliday <ghalliday@hpccsystems.com>

system/jlib/jthread.hpp

@@ -268,7 +268,7 @@ interface IPipeProcess: extends IInterface
     virtual bool run(const char *title,const char *prog, const char *dir,
                        bool hasinput,bool hasoutput,bool haserror=false,
                        size32_t stderrbufsize=0,                      // set to non-zero to automatically buffer stderror output
-                       bool newProcessGroup=false) = 0;
+                       bool newProcessGroup=false) __attribute__ ((warn_unused_result)) = 0;
     virtual bool hasInput() = 0;                                    // i.e. can write to pipe
     virtual size32_t write(size32_t sz, const void *buffer) = 0;    // write pipe process standard output
     virtual bool hasOutput() = 0;                                   // i.e. can read from pipe