DosCwait

typedef struct _RESULTCODES {  /* resc */
 
  USHORT codeTerminate;        /* Termination Code */
  USHORT codeResult;           /* Exit Code */
 
} RESULTCODES;

#define INCL_DOSPROCESS

USHORT  rc = DosCwait(ActionCode, WaitOption, ReturnCodes, ProcessIDWord,
                             ProcessID);

USHORT           ActionCode;    /* Execution options */
USHORT           WaitOption;    /* Wait options */
PRESULTCODES     ReturnCodes;   /* Termination Codes (returned) */
PPID             ProcessIDWord; /* Process ID (returned) */
PID              ProcessID;     /* Process ID of process to wait for */

USHORT           rc;            /* return code */

Example 

This example starts a child session (the program simple.exe) and then 
waits for the child process's termination. 

#define INCL_DOSPROCESS

#define START_PROGRAM "simple.exe"

CHAR        LoadError[100];
PSZ         Args;
PSZ         Envs;
RESULTCODES ReturnCodes;
USHORT      Pid;
USHORT      rc;

   strcpy(Args, "-a2 -l");             /* Pass arguments '-a2' and '-l' */
   if(!DosExecPgm(LoadError,                     /* Object name buffer */
                  sizeof(LoadError),             /* Length of object name
                                                     buffer */
                  EXEC_ASYNCRESULT,              /* Asynchronous/Trace
                                                        flags */
                  Args,                          /* Argument string */
                  Envs,                          /* Environment string */
                  &ReturnCodes,                  /* Termination codes */
                  START_PROGRAM))                /* Program file name */
      rc = DosCwait(DCWA_PROCESS,                /* Execution options */
                    DCWW_WAIT,                   /* Wait options */
                    &ReturnCodes,                /* Termination codes */
                    &Pid,                        /* Process ID */
                    ReturnCodes.codeTerminate);  /* Process ID of process
                                                     to wait for */