msvcrt
— Useful routines from the MS VC runtime¶
These functions provide access to some useful capabilities on Windows platforms.
Some higher-level modules use these functions to build the Windows
implementations of their services. For example, the getpass
module uses
this in the implementation of the getpass()
function.
Further documentation on these functions can be found in the Platform API documentation.
The module implements both the normal and wide char variants of the console I/O api. The normal API deals only with ASCII characters and is of limited use for internationalized applications. The wide char API should be used where ever possible.
File Operations¶
-
msvcrt.
locking
(fd, mode, nbytes)¶ Lock part of a file based on file descriptor fd from the C runtime. Raises
OSError
on failure. The locked region of the file extends from the current file position for nbytes bytes, and may continue beyond the end of the file. mode must be one of theLK_*
constants listed below. Multiple regions in a file may be locked at the same time, but may not overlap. Adjacent regions are not merged; they must be unlocked individually.
-
msvcrt.
LK_LOCK
¶ -
msvcrt.
LK_RLCK
¶ Locks the specified bytes. If the bytes cannot be locked, the program immediately tries again after 1 second. If, after 10 attempts, the bytes cannot be locked,
OSError
is raised.
-
msvcrt.
LK_NBLCK
¶ -
msvcrt.
LK_NBRLCK
¶ Locks the specified bytes. If the bytes cannot be locked,
OSError
is raised.
-
msvcrt.
LK_UNLCK
¶ Unlocks the specified bytes, which must have been previously locked.
-
msvcrt.
setmode
(fd, flags)¶ Set the line-end translation mode for the file descriptor fd. To set it to text mode, flags should be
os.O_TEXT
; for binary, it should beos.O_BINARY
.
-
msvcrt.
open_osfhandle
(handle, flags)¶ Create a C runtime file descriptor from the file handle handle. The flags parameter should be a bitwise OR of
os.O_APPEND
,os.O_RDONLY
, andos.O_TEXT
. The returned file descriptor may be used as a parameter toos.fdopen()
to create a file object.
Console I/O¶
-
msvcrt.
kbhit
()¶ Return
True
if a keypress is waiting to be read.
-
msvcrt.
getch
()¶ Read a keypress and return the resulting character as a byte string. Nothing is echoed to the console. This call will block if a keypress is not already available, but will not wait for Enter to be pressed. If the pressed key was a special function key, this will return
'\000'
or'\xe0'
; the next call will return the keycode. The Control-C keypress cannot be read with this function.
-
msvcrt.
getche
()¶ Similar to
getch()
, but the keypress will be echoed if it represents a printable character.
-
msvcrt.
putch
(char)¶ Print the byte string char to the console without buffering.