What is the meaning of cd. > for creating empty file in windows CMD?

Question

"What is the meaning of cd. > for creating empty file in windows CMD?" In my view point CD means change directory but why i have to put .> for creating empty file in windows CMD?

C:\Users\smith\Desktop\web>cd. >index.html

Related: [How to create an empty file at the command line in Windows?](https://stackoverflow.com/q/1702762) and [How to create empty text file from a batch file?](https://stackoverflow.com/q/210201) Anyway, do not use `cd.` for creating an empty file! if there is a file named `cd` (no extension) in the current directory, an error arises! even if there is no such file I recommend not using this since the file system is scanned, hence this is quite slow... — aschipfl, Sep 13 '19 at 11:08

score 3 · Answer 1 · answered Sep 12 '19 at 17:46

3

An alternative way to create a zero (0) length file. This seems more explicit and probably more quickly understood.

COPY NUL nnn.txt

or

TYPE NUL >nnn2.txt

answered Sep 12 '19 at 17:46

lit

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What is the meaning of COPY NUL? – sumon Sep 13 '19 at 03:53
2

@sumon, `nul` is the Null device in Windows, so you can put data into it to dismiss it or read data from it to get, well, nothing... – aschipfl Sep 13 '19 at 11:12
`NUL` on DOS/Windows is like `/dev/null` on Linux/*NIX. – lit Sep 13 '19 at 13:43

score 1 · Accepted Answer · answered Sep 12 '19 at 16:08

> redirects output from the preceding operation to a file handle. Unfortunately, there's no straighforward way to output an empty string with echo in cmd, so if you use:

echo. > newfile.txt

for example, you end up with newfile.txt containing a trailing new-line.

cd. "changes" the location to, well, the current location (so effectively does nothing) and then it outputs... well, nothing! The effect being that:

cd. > newfile.txt

results in an empty text file

What is the meaning of cd. > for creating empty file in windows CMD?

2 Answers2