On Fri, 16 Jan 2004, Jan Eden wrote:
>
> >
> >if (`file $file` =~ /JPEG/) {
> > print "$file appears to be a JPEG file.\n";
> >} else {
> > print "$file does not appear to be a JPEG file.\n";
> >}
> >
> This will tell you if the filename contains a certain string. That does
> not make the file a valid image file (besides, there's .jpg and .jpeg,
> both in uppercase and lowercase, so your pattern should be:
>
> /jpe?g/i
>
> if you just want to check the name.
>
> - Jan
>
Not true in UNIX. Maybe in Windows, I don't know. Please notice the
"backticks" which execute the "file" command. The "file" command in Linux
examines the file in the command line and sends a single line indicating
its opinion of what type of file the specified file is. It actually reads
the file looking for "markers" of some sort. If the file is a JPEG file,
then the response from the "file" command will contain the string JPEG (in
upper case), which is what I test for.
This only works, as best as I know, on a UNIX system. Windows doesn't have
this command, or it works differently. I don't do Windows.
--
--
Maranatha!
John McKown
--
To unsubscribe, e-mail: [EMAIL PROTECTED]
For additional commands, e-mail: [EMAIL PROTECTED]
<http://learn.perl.org/> <http://learn.perl.org/first-response>
