A program that Linux determines whether the process is already running

1   BOOL2 serverprocess::isalreadyrunning ()3   {4 #ifndef __linux__5Warninglog (<<"can ' t check if process already running on the platform (not implemented yet)");6      return false;7   #else8      if(mpidfile.size () = =0)9      {Ten         //if no PID file specified, we don't make an any check One         return false; A      } -    - pid_t running_pid; theStd::ifstream _pid (Mpidfile.c_str (), Std::ios_base::inch); -      if(!_pid.good ()) -      { -         //if the file doesn ' t exist or can ' t be opened, just ignore +         return false; -      } +_pid >>Running_pid; A _pid.close (); at    -Stacklog (<< mpidfile <<"contains PID"<<running_pid); -    -Data Ourproc = data ("/proc/self/exe"); -Data Otherproc = data ("/proc/") + data (running_pid) + data ("/exe"); -      Charour_exe[513], other_exe[513]; in      intbuf_size; -    toBuf_size = Readlink (Ourproc.c_str (), Our_exe, +); +      if(Buf_size <0|| Buf_size = = +) -      { the         //If Readlink fails, just ignore *         return false; $      }Panax NotoginsengOur_exe[buf_size] =0; -    theBuf_size = Readlink (Otherproc.c_str (), Other_exe, +); +      if(Buf_size <0|| Buf_size = = +) A      { the         //If Readlink fails, just ignore +         return false; -      } $Other_exe[buf_size] =0; $    -      if(strcmp (Our_exe, other_exe) = =0) -      { theErrLog (<<"already running PID:"<<running_pid); -         return true;Wuyi      } the      return false; -   #endif Wu}

A program that Linux determines whether the process is already running