Starts a program in new window, or opens a document. Uses an unclear algorithm to determine whether the first passed argument is a window title or a program to be executed; hypothesis: it uses the presence of quotes around the first argument as a hint that it is a window title.
- start notepad.exe & echo "Done."
- Starts notepad.exe, proceeding to the next command without waiting for finishing the started one. Keywords: asynchronous.
- start "notepad.exe"
- Launches a new console window with notepad.exe being its title, apparently an undesired outcome.
- start "" "C:\Program Files\Internet Explorer\iexplore.exe"
- Starts Internet Explorer. The empty "" passed as the first argument is the window title of a console that actually does not get opened, or at least not visibly so.
- start "C:\Program Files\Internet Explorer\iexplore.exe"
- Launches a new console window with "C:\Program Files\Internet Explorer\iexplore.exe" being its title, apparently an undesired outcome.
- start /wait notepad.exe & echo "Done."
- Starts notepad.exe, waiting for it to end before proceeding.
- start /low notepad.exe & echo "Done."
- As above, but starting the program with a low priority.
- start "" MyFile.xls
- Opens the document in the program assigned to open it.
- Starts a new console (command-line window) in the same current folder.
- start .
- Opens the current folder in Windows Explorer.
- start ..
- Opens the parent folder in Windows Explorer.
- start "" "mailto:"
- Starts the application for writing a new email.
- start "" "mailto:email@example.com?subject=Notification&body=Hello Joe, I'd like to..."
- Starts the application for writing a new email, specifying the to, subject and body of the new email.
- start "" "mailto:firstname.lastname@example.org?subject=Notification&body=Hello Joe,%0a%0aI'd like to..."
- As above, with newlines entered as %0a.
- start /b TODO:example-application-where-this-is-useful
- Starts the application without opening a new console window, redirecting the output to the console from which the start command was called.
- start at ss64.com
- start at Microsoft
- How to use command line switches to create a pre-addressed e-mail message in Outlook, support.microsoft.com
$ start /?
Starts a separate window to run a specified program or command.
START ["title"] [/D path] [/I] [/MIN] [/MAX] [/SEPARATE | /SHARED]
[/LOW | /NORMAL | /HIGH | /REALTIME | /ABOVENORMAL | /BELOWNORMAL]
[/NODE <NUMA node>] [/AFFINITY <hex affinity mask>] [/WAIT] [/B]
"title" Title to display in window title bar.
path Starting directory.
B Start application without creating a new window. The
application has ^C handling ignored. Unless the application
enables ^C processing, ^Break is the only way to interrupt
I The new environment will be the original environment passed
to the cmd.exe and not the current environment.
MIN Start window minimized.
MAX Start window maximized.
SEPARATE Start 16-bit Windows program in separate memory space.
SHARED Start 16-bit Windows program in shared memory space.
LOW Start application in the IDLE priority class.
NORMAL Start application in the NORMAL priority class.
HIGH Start application in the HIGH priority class.
REALTIME Start application in the REALTIME priority class.
ABOVENORMAL Start application in the ABOVENORMAL priority class.
BELOWNORMAL Start application in the BELOWNORMAL priority class.
NODE Specifies the preferred Non-Uniform Memory Architecture (NUMA)
node as a decimal integer.
AFFINITY Specifies the processor affinity mask as a hexadecimal number.
The process is restricted to running on these processors.
The affinity mask is interpreted differently when /AFFINITY and
/NODE are combined. Specify the affinity mask as if the NUMA
node's processor mask is right shifted to begin at bit zero.
The process is restricted to running on those processors in
common between the specified affinity mask and the NUMA node.
If no processors are in common, the process is restricted to
running on the specified NUMA node.
WAIT Start application and wait for it to terminate.
NEWWINDOW Instead of starting application in a new tab, start it in a new
If it is an internal cmd command or a batch file then
the command processor is run with the /K switch to cmd.exe.
This means that the window will remain after the command
has been run.
If it is not an internal cmd command or batch file then
it is a program and will run as either a windowed application
or a console application.
parameters These are the parameters passed to the command/program.
NOTE: The SEPARATE and SHARED options are not supported on 64-bit platforms.
Specifying /NODE allows processes to be created in a way that leverages memory
locality on NUMA systems. For example, two processes that communicate with
each other heavily through shared memory can be created to share the same
preferred NUMA node in order to minimize memory latencies. They allocate
memory from the same NUMA node when possible, and they are free to run on
processors outside the specified node.
start /NODE 1 application1.exe
start /NODE 1 application2.exe
These two processes can be further constrained to run on specific processors
within the same NUMA node. In the following example, application1 runs on the
low-order two processors of the node, while application2 runs on the next two
processors of the node. This example assumes the specified node has at least
four logical processors. Note that the node number can be changed to any valid
node number for that computer without having to change the affinity mask.
start /NODE 1 /AFFINITY 0x3 application1.exe
start /NODE 1 /AFFINITY 0xc application2.exe
If Command Extensions are enabled, external command invocation
through the command line or the START command changes as follows:
non-executable files may be invoked through their file association just
by typing the name of the file as a command. (e.g. WORD.DOC would
launch the application associated with the .DOC file extension).
See the ASSOC and FTYPE commands for how to create these
associations from within a command script.
When executing an application that is a 32-bit GUI application, CMD.EXE
does not wait for the application to terminate before returning to
the command prompt. This new behavior does NOT occur if executing
within a command script.
When executing a command line whose first token is the string "CMD "
without an extension or path qualifier, then "CMD" is replaced with
the value of the COMSPEC variable. This prevents picking up CMD.EXE
from the current directory.
When executing a command line whose first token does NOT contain an
extension, then CMD.EXE uses the value of the PATHEXT
environment variable to determine which extensions to look for
and in what order. The default value for the PATHEXT variable
Notice the syntax is the same as the PATH variable, with
semicolons separating the different elements.
When searching for an executable, if there is no match on any extension,
then looks to see if the name matches a directory name. If it does, the
START command launches the Explorer on that path. If done from the
command line, it is the equivalent to doing a CD /D to that path.