how to clear a file's content?

iclinux · 07-03-2005, 07:03 AM

is there any api to use?

Regards.

jcliburn · 07-03-2005, 07:14 AM

I'm not quite sure what you have in mind, but one way to empty a file is:

Code:

$ /bin/echo "" > filename

cs-cam · 07-03-2005, 07:24 AM

Or if you want to jumble it up and make the contents unretreivable:

Code:

cat /dev/urandom > filename

Just hit Ctrl-C after a second or so or you'll find yourself with a pretty large file or crap. I just tried that and it's sort of fun

iclinux · 07-03-2005, 07:31 AM

thanks, both.
BTW, is there any c API?

Michael Johnson · 07-03-2005, 07:36 AM

Just open the file in write only mode and it will be truncated to a length of 0.
#man fopen
will give you the full details

jcliburn · 07-03-2005, 07:55 AM

Quote:

Originally posted by iclinux
thanks, both.
BTW, is there any c API?

Now I understand, I think. You want to do this in C. Examine the manpage for fopen. You'll need to open the file in write mode, not append mode. For example:

Code:

fopen ("path_to_file", "w");

Opening the file this way will zero its contents.

Michael Johnson · 07-03-2005, 05:57 PM

You got it.

ursusca · 03-30-2009, 02:01 PM

echo -n > file