Re: [Libguestfs] [PATCH 2/2] daemon: Remove redundant fork in commandrvf
On Thu, Dec 13, 2012 at 03:22:39PM +0000, Matthew Booth wrote:
Currently the code is doing a redundant fork when passed the
COMMAND_FLAG_CHROOT_COPY_FILE_TO_STDIN flag. The additional sub-process does a
chroot() which has no effect because all file handles are already open at that
point, then simply copies its input to its output.
This change simply replaces the above with a dup2 of the passed file handle to
STDIN of the command process.
NACK. This removes the chroot call, so I don't see how it can
be right.
Did you read the comment and the linked bug?
* COMMAND_FLAG_CHROOT_COPY_FILE_TO_STDIN: For running external
* commands on chrooted files correctly (see RHBZ#579608) specifying
* this flag causes another process to be forked which chroots into
* sysroot and just copies the input file to stdin of the specified
* command. The file descriptor is ORed with the flags, and that file
* descriptor is always closed by this function. See hexdump.c for an
* example of usage.
https://bugzilla.redhat.com/show_bug.cgi?id=579608
Rich.
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