How to create an empty file at the command line in Windows?
How to create an empty file at the DOS/Windows command-line?
I tried:
copy nul > file.txt
but it always displays that a file was copied.
Is there any other method in the standard cmd?
It should be a method that does not require the touch command from Cygwin or any other nonstandard commands. The command needs to run from a script so keystrokes cannot be used.
Without redirection, Luc Vu or Erik Konstantopoulos point out to:
copy NUL EMptyFile.txt
copy /b NUL EmptyFile.txt
"How to create empty text file from a batch file?" (2008) also points to:
type NUL > EmptyFile.txt
# also
echo. 2>EmptyFile.txt
copy nul file.txt > nul # also in qid's answer below
REM. > empty.file
fsutil file createnew file.cmd 0 # to create a file on a mapped drive
Nomad mentions an original one:
C:UsersVonCprogtests>aaaa > empty_file
'aaaa' is not recognized as an internal or external command, operable program or batch file.
C:UsersVonCprogtests>dir
Folder C:UsersVonCprogtests
27/11/2013 10:40 <REP> .
27/11/2013 10:40 <REP> ..
27/11/2013 10:40 0 empty_file
In the same spirit, Samuel suggests in the comments:
the shortest one I use is basically the one by Nomad:
.>out.txt
It does give an error:
'.' is not recognized as an internal or external command
But this error is on stderr. And > only redirects stdout, where nothing have been produced.
Hence the creation of an empty file. The error message can be disregarded here.
(Original answer, November 2009)
echo.>filename
( echo "" would actually put "" in the file! And echo without the '.' would put " Command ECHO activated " in the file...)
Note: the resulting file is not empty but includes a return line sequence: 2 bytes.
This discussion points to a true batch solution for a real empty file:
<nul (set/p z=) >filename
dir filename
11/09/2009 19:45 0 filename
1 file(s) 0 bytes
The " <nul " pipes a nul response to the set/p command, which will cause the variable used to remain unchanged. As usual with set/p , the string to the right of the equal sign is displayed as a prompt with no CRLF.
Since here the "string to the right of the equal sign" is empty... the result is an empty file.
The difference with cd. > filename cd. > filename (which is mentioned in Patrick Cuff's answer and does also produce a 0-byte-length file) is that this "bit of redirection" (the <nul... trick) can be used to echo lines without any CR :
<nul (set/p z=hello) >out.txt
<nul (set/p z= world!) >>out.txt
dir out.txt
The dir command should indicate the file size as 12 bytes: " hello world! ".
Try this:
type NUL > 1.txt
this will definitely create an empty file.
这是另一种方式：
cd. > filename