_spawnlp, _wspawnlp

Creates and executes a new process.


This API cannot be used in applications that execute in the Windows Runtime. For more information, see CRT functions not supported with /ZW.

intptr_t _spawnlp(
   int mode,
   const char *cmdname,
   const char *arg0,
   const char *arg1,
   ... const char *argn,
intptr_t _wspawnlp(
   int mode,
   const wchar_t *cmdname,
   const wchar_t *arg0,
   const wchar_t *arg1,
   ... const wchar_t *argn,


  • mode
    Execution mode for the calling process.

  • cmdname
    Path of the file to be executed.

  • arg0, arg1, ... argn
    List of pointers to arguments. The arg0 argument is usually a pointer to cmdname. The arguments arg1 through argn are pointers to the character strings forming the new argument list. Following argn, there must be a NULL pointer to mark the end of the argument list.

Return Value

The return value from a synchronous _spawnlp or _wspawnlp (_P_WAIT specified for mode) is the exit status of the new process. The return value from an asynchronous _spawnlp or _wspawnlp (_P_NOWAIT or _P_NOWAITO specified for mode) is the process handle. The exit status is 0 if the process terminated normally. You can set the exit status to a nonzero value if the spawned process specifically calls the exit routine with a nonzero argument. If the new process did not explicitly set a positive exit status, a positive exit status indicates an abnormal exit with an abort or an interrupt. A return value of –1 indicates an error (the new process is not started). In this case, errno is set to one of the following values.

  • E2BIG
    Argument list exceeds 1024 bytes.

    mode argument is invalid.

    File or path is not found.

    Specified file is not executable or has invalid executable-file format.

    Not enough memory is available to execute the new process.

For more information about these and other return codes, see _doserrno, errno, _sys_errlist, and _sys_nerr.


Each of these functions creates and executes a new process, passing each command-line argument as a separate parameter and using the PATH environment variable to find the file to execute.

These functions validate their parameters. If either cmdname or arg0 is an empty string or a null pointer, these functions generate an invalid parameter exception, as described in Parameter Validation. If execution is allowed to continue, these functions set errno to EINVAL, and return -1. No new process is spawned.



Required header




<stdio.h> or <wchar.h>

For more compatibility information, see Compatibility in the Introduction.


See the example in _spawn, _wspawn Functions.

.NET Framework Equivalent

See Also


Process and Environment Control

_spawn, _wspawn Functions



_exec, _wexec Functions

exit, _exit



_onexit, _onexit_m


system, _wsystem