locking failed for /home/whoever/.zhistory: no such file or directory

locking failed for /home/whoever/.zhistory: no such file or directory

[Cesar Romani]

I'm using zsh 4.3.12-dev-1
Whenever I start zsh I always get the following message:
zsh: locking failed for /home/whoever/.zhistory: no such file or 
directory: reading anyway

and when I exit the shell I get:
zsh: locking failed for /home/whoever/.zhistory: no such file or directory

But the file .zhistory is present on my system, on /home/whoever and my
HOME is set to /home/whoever
I tried to delete and create .zhistory again, but it's no use.
On my .zshrc I have, among other things:

export HISTSIZE=200
export HISTFILE=~/.zhistory
export SAVEHIST=200

Many thanks in advance,

-- 
Cesar

Re: locking failed for /home/whoever/.zhistory: no such file or directory

[Peter Stephenson]

Cesar Romani wrote:
> I'm using zsh 4.3.12-dev-1
> Whenever I start zsh I always get the following message:
> zsh: locking failed for /home/whoever/.zhistory: no such file or 
> directory: reading anyway

That means a system call to lock the file for reading failed.  It
depends on the file system whether locking is enabled.  So long as you
are not attempting to use the history file with multiple terminals at
once, you shouldn't hit problems.

-- 
Peter Stephenson <p.w.stephenson@ntlworld.com>
Web page now at http://homepage.ntlworld.com/p.w.stephenson/

Re: locking failed for /home/whoever/.zhistory: no such file or directory

[Bart Schaefer]

On Jul 10,  9:22am, Cesar Romani wrote:
} Subject: locking failed for /home/whoever/.zhistory: no such file or direc
}
} I'm using zsh 4.3.12-dev-1
} Whenever I start zsh I always get the following message:
} zsh: locking failed for /home/whoever/.zhistory: no such file or 
} directory: reading anyway

This probably means that your system doesn't support zsh's preferred
form of locking, so zsh is trying to create a file in the directory
named by your $TMPPREFIX.  Does *that* directory exist?  What do you
see if you run

    print =(:)

?  Do you change TMPPREFIX at any time in your startup files?

Re: locking failed for /home/whoever/.zhistory: no such file or directory

[Cesar Romani]

On 10/07/2011 11:53 a.m., Peter Stephenson wrote:
 > Cesar Romani wrote:
 >> I'm using zsh 4.3.12-dev-1
 >> Whenever I start zsh I always get the following message:
 >> zsh: locking failed for /home/whoever/.zhistory: no such file or
 >> directory: reading anyway
 >
 > That means a system call to lock the file for reading failed.  It
 > depends on the file system whether locking is enabled.  So long as you
 > are not attempting to use the history file with multiple terminals at
 > once, you shouldn't hit problems.

But my .zhistory is always empty. Isn't there a workaround for it?
With zsh 4.3.10 I didn't have that problem.

Best regards,

-- 
Cesar

Re: locking failed for /home/whoever/.zhistory: no such file or directory

[Peter Stephenson]

On Wed, 13 Jul 2011 08:50:07 -0500
Cesar Romani <cesar.romani@gmail.com> wrote:
> On 10/07/2011 11:53 a.m., Peter Stephenson wrote:
>  > Cesar Romani wrote:
>  >> I'm using zsh 4.3.12-dev-1
>  >> Whenever I start zsh I always get the following message:
>  >> zsh: locking failed for /home/whoever/.zhistory: no such file or
>  >> directory: reading anyway
>  >
>  > That means a system call to lock the file for reading failed.  It
>  > depends on the file system whether locking is enabled.  So long as you
>  > are not attempting to use the history file with multiple terminals at
>  > once, you shouldn't hit problems.
> 
> But my .zhistory is always empty. Isn't there a workaround for it?
> With zsh 4.3.10 I didn't have that problem.

You did have the problem, but the shell didn't warn you it wasn't going
to be able to manage history safely.

Is there a good reason you need to have the .zhistory file even though
it's empty?  If not, delete it, or if this means you aren't using
history files at all unset HISTFILE in ~/.zshrc.

If there's a good reason to have a valid HISTFILE variable pointing to a
file that's empty, we can add a special case to test for a zero file
before reading, but I can't offhand think of a case why you need this.

-- 
Peter Stephenson <pws@csr.com>            Software Engineer
Tel: +44 (0)1223 692070                   Cambridge Silicon Radio Limited
Churchill House, Cambridge Business Park, Cowley Road, Cambridge, CB4 0WZ, UK



Member of the CSR plc group of companies. CSR plc registered in England and Wales, registered number 4187346, registered office Churchill House, Cambridge Business Park, Cowley Road, Cambridge, CB4 0WZ, United Kingdom
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Re: locking failed for /home/whoever/.zhistory: no such file or directory

[Bart Schaefer]

On Jul 13,  3:01pm, Peter Stephenson wrote:
} Subject: Re: locking failed for /home/whoever/.zhistory: no such file or d
}
} > But my .zhistory is always empty. Isn't there a workaround for it?
} > With zsh 4.3.10 I didn't have that problem.
} 
} You did have the problem, but the shell didn't warn you it wasn't going
} to be able to manage history safely.
} 
} Is there a good reason you need to have the .zhistory file even though
} it's empty?

I think he means zsh is never writing anything to the file, not that it
is intentionally always empty.

Re: locking failed for /home/whoever/.zhistory: no such file or directory

[Peter Stephenson]

On Wed, 13 Jul 2011 07:54:44 -0700
Bart Schaefer <schaefer@brasslantern.com> wrote:
> On Jul 13,  3:01pm, Peter Stephenson wrote:
> } Subject: Re: locking failed for /home/whoever/.zhistory: no such file or d
> }
> } > But my .zhistory is always empty.
> } 
> } Is there a good reason you need to have the .zhistory file even though
> } it's empty?
> 
> I think he means zsh is never writing anything to the file, not that it
> is intentionally always empty.

That's not related to the locking problem, though, is it?

It's very easy to ignore empty files completely.  We always stat anyway
in the "fast" case, so this only adds the operation in the normal case,
where an extra stat is lost in the noise.

Index: Src/hist.c
===================================================================
RCS file: /cvsroot/zsh/zsh/Src/hist.c,v
retrieving revision 1.113
diff -p -u -r1.113 hist.c
--- Src/hist.c	12 Jul 2011 08:37:11 -0000	1.113
+++ Src/hist.c	13 Jul 2011 18:50:15 -0000
@@ -2246,10 +2246,12 @@ readhistfile(char *fn, int err, int read
 
     if (!fn && !(fn = getsparam("HISTFILE")))
 	return;
+    if (stat(unmeta(fn), &sb) < 0 ||
+	sb.st_size == 0)
+	return;
     if (readflags & HFILE_FAST) {
-	if (stat(unmeta(fn), &sb) < 0
-	 || (lasthist.fsiz == sb.st_size && lasthist.mtim == sb.st_mtime)
-	 || lockhistfile(fn, 0))
+	if ((lasthist.fsiz == sb.st_size && lasthist.mtim == sb.st_mtime)
+	    || lockhistfile(fn, 0))
 	    return;
 	lasthist.fsiz = sb.st_size;
 	lasthist.mtim = sb.st_mtime;


-- 
Peter Stephenson <p.w.stephenson@ntlworld.com>
Web page now at http://homepage.ntlworld.com/p.w.stephenson/

Re: locking failed for /home/whoever/.zhistory: no such file or directory

[Bart Schaefer]

On Jul 13,  7:53pm, Peter Stephenson wrote:
} Subject: Re: locking failed for /home/whoever/.zhistory: no such file or d
}
} On Wed, 13 Jul 2011 07:54:44 -0700
} Bart Schaefer <schaefer@brasslantern.com> wrote:
} > 
} > I think he means zsh is never writing anything to the file, not that it
} > is intentionally always empty.
} 
} That's not related to the locking problem, though, is it?

It might be -- that is, they might both stem from the same underlying
cause, which is probably an issue with his system (perhaps his home
directory permissions, for example, though I'm at a loss as to the
exact reason).  But the point is that his runtime history is non-empty
and he's set SAVEHIST to a non-zero value, yet nothing is ever written
to the file, so *something* is failing, and the only error he's seeing
is the lock warning at startup.

Maybe starting a login shell ("zsh -l" for those who don't know) from
within another shell, and then exiting from that inner shell, would
provide an opportunity to see error messages that are otherwise being
hidden by the closing of a terminal emulator window or the like.