Groups: DOSPROCESS

UNI declaration:

function DosExecPgm(in pObjname: PCHAR; in cbObjname: LONG; in execFlag: ULONG; in pArg: PSZ; in pEnv: PSZ; out pRes: RESULTCODES; in pName: PSZ): APIRET;

Lets a program run another program as a child process.

Parameters:

• pObjname (PCHAR) - input. Address of the buffer in which the name of the object that contributed to the failure of DosExecPgm is returned.
• cbObjname (LONG) - input. Length, in bytes, of the buffer described by pObjname.
• execFlag (ULONG) - input. Flag indicating how the program runs in relation to the requester, and whether execution is under conditions for debugging.
• pArg (PSZ) - input. Address of the ASCIIZ argument strings passed to the program.
• pEnv (PSZ) - input. Address of the ASCIIZ environment strings passed to the program.
• pRes (RESULTCODES) - output. Pointer to the RESULTCODES structure where the process ID, or the termination code and the result code indicating the reason for ending the child process is returned.
• pName (PSZ) - input. Address of the name of the file that contains the program to be executed.

Return codes:

• NO_ERROR
• ERROR_INVALID_FUNCTION
• ERROR_FILE_NOT_FOUND
• ERROR_PATH_NOT_FOUND
• ERROR_TOO_MANY_OPEN_FILES
• ERROR_ACCESS_DENIED
• ERROR_NOT_ENOUGH_MEMORY
• ERROR_BAD_ENVIRONMENT
• ERROR_BAD_FORMAT
• ERROR_INVALID_DATA
• ERROR_NOT_DOS_DISK
• ERROR_GEN_FAILURE
• ERROR_SHARING_VIOLATION
• ERROR_LOCK_VIOLATION
• ERROR_SHARING_BUFFER_EXCEEDED
• ERROR_NO_PROC_SLOTS
• ERROR_INTERRUPT
• ERROR_DRIVE_LOCKED
• ERROR_PROC_NOT_FOUND
• ERROR_INVALID_ORDINAL
• ERROR_INVALID_MODULETYPE
• ERROR_INVALID_EXE_SIGNATURE
• ERROR_EXE_MARKED_INVALID
• ERROR_INVALID_MINALLOCSIZE
• ERROR_DYNLINK_FROM_INVALID_RING

For a full list of error codes, see Errors.

 #define INCL_DOSPROCESS       /* Process and thread values */
 
 #define INCL_DOS
 
 #define INCL_DOSERRORS        /* DOS error values          */
 
 #include <os2.h>
 
 #include <stdio.h>
 
 
 
 int main(VOID) {
 
 UCHAR       LoadError[CCHMAXPATH] = {0};
 
 PSZ         Args             = NULL;
 
 PSZ         Envs             = NULL;
 
 RESULTCODES ChildRC          = {0};
 
 APIRET      rc               = NO_ERROR;  /* Return code */
 
 
 
   rc = DosExecPgm(LoadError,           /* Object name buffer           */
 
                   sizeof(LoadError),   /* Length of object name buffer */
 
                   EXEC_SYNC,           /* Asynchronous/Trace flags     */
 
                   Args,                /* Argument string              */
 
                   Envs,                /* Environment string           */
 
                   &ChildRC,            /* Termination codes            */
 
                   "qfsinfo.exe");      /* Program file name            */
 
 
 
   if (rc != NO_ERROR) {
 
      printf("DosExecPgm error: return code = %u\n",rc);
 
      return 1;
 
   } else {
 
      printf("DosExecPgm complete.  Termination Code: %u  Return Code: %u\n",
 
              ChildRC.codeTerminate,
 
              ChildRC.codeResult);  /* This is explicitly set by other pgm */
 
   } /* endif */
 
 
 
   return NO_ERROR;
 
   }

 
 #define INCL_DOSPROCESS       /* Process and thread values */
 
 #define INCL_DOSERRORS        /* DOS error values          */
 
 #define INCL_DOS
 
 #include <os2.h>
 
 #include <stdio.h>
 
 
 
 int main(VOID) {
 
 UCHAR       uchLoadError[CCHMAXPATH] = {0}; /* Error info from DosExecPgm */
 
 RESULTCODES ChildRC           = {0};       /* Results from child process  */
 
 PID         pidChild          = 0;         /* pid for child process       */
 
 APIRET      rc                = NO_ERROR;  /* Return code                 */
 
 UCHAR       uchEnvString[14]  = "ANYTHING=HERE\0";  /* Environment string */
 
 UCHAR       uchArgString[14]  = "CHKDSK\0 C: \0";   /* Argument string    */
 
 
 
       /* The argument string consists of the following:
 
             - the name of the program (followed by a NULL)
 
             - any parameters supplied to the program (followed by 2 NULLs)
 
          Only 1 NULL is explicitly specified at the end of this string.
 
          ASCIIZ strings end with a NULL already, giving us 2 NULLs.       */
 
 
 
   rc = DosExecPgm(uchLoadError,           /* Object name buffer           */
 
                   sizeof(uchLoadError),   /* Length of object name buffer */
 
                   EXEC_ASYNCRESULT,       /* Asynchronous/Trace flags     */
 
                   uchArgString,           /* Argument string              */
 
                   uchEnvString,           /* Environment string           */
 
                   &ChildRC,               /* Returns pid of process on an
 
                                              asynchronous request         */
 
                   "CHKDSK.COM");          /* Program file name            */
 
 
 
   if (rc != NO_ERROR) {
 
      printf("DosExecPgm error: return code = %u\n",rc);
 
      return 1;
 
   }
 
 
 
   rc = DosWaitChild(DCWA_PROCESS,    /* Look at only the process specified */
 
                     DCWW_WAIT,       /* Wait until a child terminates      */
 
                     &ChildRC,        /* Termination codes returned         */
 
                     &pidChild,       /* pid of terminating process         */
 
                     ChildRC.codeTerminate);   /* Process (pid) to look at  */
 
 
 
   if (rc != NO_ERROR) {
 
      printf("DosWaitChild error: return code = %u\n",rc);
 
      return 1;
 
   } else {
 
      printf("Child complete.  Termination Code: %u  Return Code: %u\n",
 
              ChildRC.codeTerminate, ChildRC.codeResult);
 
   }
 
   return NO_ERROR;
 
  }