Check whether a file exists

How can I check whether a file exists?

Jul 30 '06 #1

11098

"sword" <so***********@ gmail.comwrote in message
news:11******** ************@m7 3g2000cwd.googl egroups.com...
: How can I check whether a file exists?

You'll get the same answer here as in the C NG ;)

The portable way to check for this is to try to open
the file (you may use ifstream, or fopen as in C)
to check if it succeeds, then close it immediately.

Two main issues are:
- various operating systems may have various
restrictions on visibility or accessibility
of files within a given storage/directory.
- on a multitasking OS, a file that exists
at a given time may be deleted by the next
statement.

So in general, best is to just try to use the file,
and report the error at that point.
hth-Ivan
--
http://ivan.vecerina.com/contact/?subject=NG_POST <- email contact form
Brainbench MVP for C++ <http://www.brainbench.com

Jul 30 '06 #2

Bruintje Beer

"sword" <so***********@ gmail.comschree f in bericht
news:11******** ************@m7 3g2000cwd.googl egroups.com...

How can I check whether a file exists?

man access

John

Jul 30 '06 #3

sword

Thanks

Jul 30 '06 #4

Jakob Bieling

Bruintje Beer <me@knoware.nlw rote:

"sword" <so***********@ gmail.comschree f in bericht
news:11******** ************@m7 3g2000cwd.googl egroups.com...

>How can I check whether a file exists?

man access

Are you aware of the fact this will not lead to any solution to the
problem at all in many cases?
--
jb

(reply address in rot13, unscramble first)

Jul 30 '06 #5

Moonlit

Hi,

On most platforms there is a function called fstat, stat and lstat that uses
a filename, or descriptor and lets you check for various stuff about a file
(I believe it returns
'-1' if a file doesn't exist) Available on linux, solaris, windows, dec and
probably many more.
--
Regards, Ron AF Greve

http://moonlit.xs4all.nl

"sword" <so***********@ gmail.comwrote in message
news:11******** ************@m7 3g2000cwd.googl egroups.com...

How can I check whether a file exists?

Jul 30 '06 #6

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