Bugtraq mailing list archives
Re: Changes to the filesystem while find is running - comments?
From: Martin Buchholz <Martin.Buchholz () Sun COM>
Date: Wed, 24 Nov 2004 09:25:32 -0800
Casper.Dik () Sun COM wrote:
I can see that that would be useful but it would fail to comply with the POSIX standard, which specifies: The find utility shall be able to descend to arbitrary depths in a file hierarchy and shall not fail due to path length limitations (unless a path operand specified by the application exceeds {PATH_MAX} requirements)
But PATH_MAX is limited and the number of file descriptors is perhaps not. (On Solaris, PATH_MAX is 1024 so you require at most 512 file descriptors to keep the stack of directories: 512 is less than the default hard limit of 65536 file descriptors per process [S9, S8 and before used 1024, still >> 512)
My reading of the above paragraph from the POSIX standard is that find is required to be able to traverse arbitrary depths, even when the resulting path length exceeds PATH_MAX. On my Solaris 9 system, the default file descriptor limit appears to be 256. I am genuinely surprised that Solaris still has such a relatively small PATH_MAX. Linux has 4096. Like other arbitrary system limits of its ilk, PATH_MAX is evil, and is one of the more persuasive arguments for getting rid of the C language and its fixed-size stack-allocated buffers. char path[PATH_MAX]; /* considered harmful */ Martin
Casper
Current thread:
- Changes to the filesystem while find is running - comments? James Youngman (Nov 22)
- Re: Changes to the filesystem while find is running - comments? Martin Buchholz (Nov 22)
- Re: Changes to the filesystem while find is running - comments? Dmitry V. Levin (Nov 22)
- Re: Changes to the filesystem while find is running - comments? James Youngman (Nov 23)
- Re: Changes to the filesystem while find is running - comments? Martin Buchholz (Nov 23)
- Re: Changes to the filesystem while find is running - comments? James Youngman (Nov 23)
- Re: Changes to the filesystem while find is running - comments? Martin Buchholz (Nov 23)
- Re: Changes to the filesystem while find is running - comments? devnull (Nov 24)
- Re: Changes to the filesystem while find is running - comments? Casper . Dik (Nov 24)
- Re: Changes to the filesystem while find is running - comments? Martin Buchholz (Nov 24)
- Re: Changes to the filesystem while find is running - comments? Casper . Dik (Nov 24)
- Re: Changes to the filesystem while find is running - comments? Martin Buchholz (Nov 22)
- Re: Changes to the filesystem while find is running - comments? James Youngman (Nov 25)
- <Possible follow-ups>
- Re: Changes to the filesystem while find is running - comments? Paul Szabo (Nov 23)
- Re: Changes to the filesystem while find is running - comments? James Youngman (Nov 23)
- Re: Changes to the filesystem while find is running - comments? Paul Szabo (Nov 23)
- Re: Changes to the filesystem while find is running - comments? Martin Buchholz (Nov 23)
- Re: Changes to the filesystem while find is running - comments? Paul Szabo (Nov 23)
- Re: Changes to the filesystem while find is running - comments? James Youngman (Nov 23)