Problem with File.exists? giving an incorrect result

[Chris Dwan]

I have a problem with a script I'm working on. File.exists? is
telling me that a file does in fact exist, then immediately after
when I try to do a File.read, it crashes because the file doesn't
exist. I know that it does not exist, because I'm testing that
condition. If the file doesn't exist, it should do something else.

<sigh> this is on Windows, so maybe the OS is to blame?
Here's the code, if it helps..

$debug_log.fatal("does file exist? :: #{ibl}")
if File.exist?(ibl)
$debug_log.fatal("YES - it most certainlyt does!")
iblLocation = ibl
else
#find the file and set iblLocation
end
File.read(iblLocation) # << bombs here

The file referred to by ibl was recently renamed by this same script,
so the file name in ibl is no longer valid. The script should then go
looking for ibl's new name and use that... but it won't work <sob><sob>

Hope someone can enlighten me.
Thanks!

 

[Sharon Phillips]

I have a problem with a script I'm working on. File.exists? is
telling me that a file does in fact exist, then immediately after
when I try to do a File.read, it crashes because the file doesn't
exist. I know that it does not exist, because I'm testing that
condition. If the file doesn't exist, it should do something else.

<sigh> this is on Windows, so maybe the OS is to blame?
Here's the code, if it helps..

$debug_log.fatal("does file exist? :: #{ibl}")
if File.exist?(ibl)
$debug_log.fatal("YES - it most certainlyt does!")
iblLocation = ibl
else
#find the file and set iblLocation
end
File.read(iblLocation) # << bombs here

The file referred to by ibl was recently renamed by this same
script, so the file name in ibl is no longer valid. The script
should then go looking for ibl's new name and use that... but it
won't work <sob><sob>

Hope someone can enlighten me.
Thanks!

I assume you have permission to read the file?

 

[John Joyce]

I have a problem with a script I'm working on. File.exists? is
telling me that a file does in fact exist, then immediately after
when I try to do a File.read, it crashes because the file doesn't
exist. I know that it does not exist, because I'm testing that
condition. If the file doesn't exist, it should do something else.

<sigh> this is on Windows, so maybe the OS is to blame?
Here's the code, if it helps..

$debug_log.fatal("does file exist? :: #{ibl}")
if File.exist?(ibl)
$debug_log.fatal("YES - it most certainlyt does!")
iblLocation = ibl
else
#find the file and set iblLocation
end
File.read(iblLocation) # << bombs here

The file referred to by ibl was recently renamed by this same
script, so the file name in ibl is no longer valid. The script
should then go looking for ibl's new name and use that... but it
won't work <sob><sob>

Hope someone can enlighten me.
Thanks!

You need to open the file first.
File.new OR File.open
check them with ri first, you may need to choose binary or text when
setting the file mode because you're using windows

 

[Alex LeDonne]

I have a problem with a script I'm working on. File.exists? is
telling me that a file does in fact exist, then immediately after
when I try to do a File.read, it crashes because the file doesn't
exist. I know that it does not exist, because I'm testing that
condition. If the file doesn't exist, it should do something else.

<sigh> this is on Windows, so maybe the OS is to blame?
Here's the code, if it helps..

$debug_log.fatal("does file exist? :: #{ibl}")
if File.exist?(ibl)
$debug_log.fatal("YES - it most certainlyt does!")
iblLocation = ibl
else
#find the file and set iblLocation
end
File.read(iblLocation) # << bombs here

The file referred to by ibl was recently renamed by this same script,
so the file name in ibl is no longer valid. The script should then go
looking for ibl's new name and use that... but it won't work <sob><sob>

Hope someone can enlighten me.
Thanks!

What does the rename code look like? I've seen lots of weirdness on
Windows because file operations that you might think are atomic,
aren't.

-A

 

[Nobuyoshi Nakada]

Hi,

At Sun, 22 Jul 2007 19:21:19 +0900,
Chris Dwan wrote in [ruby-talk:261241]:

<sigh> this is on Windows, so maybe the OS is to blame?
Here's the code, if it helps..

$debug_log.fatal("does file exist? :: #{ibl}")
if File.exist?(ibl)
$debug_log.fatal("YES - it most certainlyt does!")
iblLocation = ibl
else
#find the file and set iblLocation
end
File.read(iblLocation) # << bombs here

What are the actual exception you get, and the version? And
$debug_log shows "YES - ..."?