Examines the /proc directory to establish all the processes currently running on the machine. The function populates a map of process ids to hzProginfo instances. Note this function will fail only if the /proc directory cannot be read or there is a duplicate entry in it. As the /proc is usually readable and executable by everyone and Linux/Unix has few bugs, neither of these events ever acually happens.

Declared in file: hzUnixacc.h
Defined in file : hzProcess.cpp

Function Logic:

Function body:

hzEcode ListProcesses (hzMapS<uint32_t,hzProginfo*>& procs)
{
   //  Category: Diagnostics
   //  
   //  Examines the /proc directory to establish all the processes currently running on the machine. The function populates a map of process ids to hzProginfo instances.
   //  
   //  Arguments: 1) procs This is a reference to a hzMapS<uint32_t,hzProginfo*> that this query function will populate.
   //  
   //  Returns: E_CORRUPT If there was an error reading the /proc directory (see note)
   //     E_OK  If the operation was successful
   //  
   //  Note this function will fail only if the /proc directory cannot be read or there is a duplicate entry in it. As the /proc is usually readable and executable by everyone and
   //  Linux/Unix has few bugs, neither of these events ever acually happens.
   _hzfunc("ListProcesses") ;
   hzProginfo* pPI ;               //  Program information (from /proc)
   FSTAT       fs ;                //  File status
   dirent*     pDE ;               //  Directory entry meta data
   DIR*        pDir ;              //  Operating directory
   uint32_t    ino ;               //  Inode number of directory entry
   uint32_t    cpid ;              //  Current process id
   uint32_t    xpid ;              //  Process id derived from sub-dirs of /proc
   uint32_t    nIndex ;            //  General iterator
   char        buf [512];          //  Directory entry name buffer
   /*
   **  ** Obtain current executable
   **      */
   //  Clear tables
   for (nIndex = 0; nIndex < procs.Count() ; nIndex++)
   {
       pPI = procs.GetObj(nIndex) ;
       delete pPI ;
   }
   procs.Clear() ;
   //  Open the /proc directory and read it.
   pDir = opendir("/proc") ;
   if (!pDir)
   {
       hzerr(E_CORRUPT, "Could not open the /proc directory") ;
       return E_CORRUPT ;
   }
   for (; pDE = readdir(pDir) ;)
   {
       //  Eliminate self
       if (pDE->d_name[0]== ''.'')
           continue ;
       //  Eliminate all non numeric directories
       if (!IsAllDigits(pDE->d_name))
           continue ;
       xpid = atoi(pDE->d_name) ;
       pPI = procs[xpid] ;
       if (pPI)
       {
           hzerr(E_SETONCE, "We already have process %d in the process list", xpid) ;
           return E_SETONCE ;
       }
       pPI = new hzProginfo() ;
       pPI->m_PID = xpid ;
       sprintf(buf, "/proc/%d/exe", xpid) ;
       if (lstat(buf, &fs) == -1)
           std::cout << "Could not stat " << buf << std::endl ;
       else
       {
           if (fs.st_ino == ino)
           {
               std::cout << "pid: " << cpid << " - Have located an existing process of " << xpid << std::endl ;
               std::cerr << "Both the existing and current process involve executable with inode of " << ino << std::endl ;
               exit(-4);
           }
       }
       procs.Insert(pPI->m_PID, pPI) ;
   }
   closedir(pDir) ;
   return E_OK ;
}