Make /sysroot path configurable.

[libguestfs.git] / guestfish.pod

diff --git a/guestfish.pod b/guestfish.pod
index 28daa0a..32a3090 100644 (file)
--- a/guestfish.pod
+++ b/guestfish.pod
@@ -8,6 +8,10 @@ guestfish - the libguestfs filesystem interactive shell
 
  guestfish [--options] [commands]
 
 
  guestfish [--options] [commands]
 

+ guestfish -i libvirt-domain
+
+ guestfish -i disk-image(s)
+

 =head1 EXAMPLES
 
 =head2 From shell scripts
 =head1 EXAMPLES
 
 =head2 From shell scripts


@@ -40,21 +44,33 @@ Remove C</boot/grub/menu.lst> (in reality not such a great idea):
  guestfish --add disk.img \
    --mount /dev/VolGroup00/LogVol00 \
    --mount /dev/sda1:/boot \
  guestfish --add disk.img \
    --mount /dev/VolGroup00/LogVol00 \
    --mount /dev/sda1:/boot \

-   rm /boot/grub/menu.lst : \
-   sync : exit
+   rm /boot/grub/menu.lst

 
 =head2 As an interactive shell
 
  $ guestfish
 
 =head2 As an interactive shell
 
  $ guestfish

- 
+

  Welcome to guestfish, the libguestfs filesystem interactive shell for
  editing virtual machine filesystems.
  Welcome to guestfish, the libguestfs filesystem interactive shell for
  editing virtual machine filesystems.

- 
+

  Type: 'help' for help with commands
        'quit' to quit the shell
  Type: 'help' for help with commands
        'quit' to quit the shell

- 
+

  ><fs> help
 
  ><fs> help
 

+=head2 As a script interpreter
+
+ #!/usr/bin/guestfish -f
+ alloc /tmp/output.img 10M
+ run
+ sfdisk /dev/sda 0 0 0 ,
+ mkfs ext2 /dev/sda1
+
+=head2 Remote control
+
+ eval `guestfish --listen`
+ guestfish --remote cmd
+

 =head1 DESCRIPTION
 
 Guestfish is a shell and command-line tool for examining and modifying
 =head1 DESCRIPTION
 
 Guestfish is a shell and command-line tool for examining and modifying


@@ -81,6 +97,50 @@ Displays detailed help on a single command C<cmd>.
 
 Add a block device or virtual machine image to the shell.
 
 
 Add a block device or virtual machine image to the shell.
 

+=item B<-D> | B<--no-dest-paths>
+
+Don't tab-complete paths on the guest filesystem.  It is useful to be
+able to hit the tab key to complete paths on the guest filesystem, but
+this causes extra "hidden" guestfs calls to be made, so this option is
+here to allow this feature to be disabled.
+
+=item B<-f file> | B<--file file>
+
+Read commands from C<file>.  To write pure guestfish
+scripts, use:
+
+ #!/usr/bin/guestfish -f
+
+=item B<-i> | B<--inspector>
+
+Run virt-inspector on the named libvirt domain or list of disk
+images.  If virt-inspector is available and if it can identify
+the domain or disk images, then partitions will be mounted
+correctly at start-up.
+
+Typical usage is either:
+
+ guestfish -i myguest
+
+(for an inactive libvirt domain called I<myguest>), or:
+
+ guestfish --ro -i myguest
+
+(for active domains, readonly), or specify the block device directly:
+
+ guestfish -i /dev/Guests/MyGuest
+
+You cannot use I<-a>, I<-m>, I<--listen> or I<--remote> in conjunction
+with this option, and options other than I<--ro> might not behave
+correctly.
+
+See also: L<virt-inspector(1)>.
+
+=item B<--listen>
+
+Fork into the background and listen for remote commands.  See section
+I<REMOTE CONTROL GUESTFISH OVER A SOCKET> below.
+

 =item B<-m dev[:mountpoint]> | B<--mount dev[:mountpoint]>
 
 Mount the named partition or logical volume on the given mountpoint.
 =item B<-m dev[:mountpoint]> | B<--mount dev[:mountpoint]>
 
 Mount the named partition or logical volume on the given mountpoint.


@@ -97,6 +157,11 @@ automatically launched.
 Disable autosync.  This is enabled by default.  See the discussion
 of autosync in the L<guestfs(3)> manpage.
 
 Disable autosync.  This is enabled by default.  See the discussion
 of autosync in the L<guestfs(3)> manpage.
 

+=item B<--remote[=pid]>
+
+Send remote commands to C<$GUESTFISH_PID> or C<pid>.  See section
+I<REMOTE CONTROL GUESTFISH OVER A SOCKET> below.
+

 =item B<-r> | B<--ro>
 
 This changes the C<-m> option so that mounts are done read-only
 =item B<-r> | B<--ro>
 
 This changes the C<-m> option so that mounts are done read-only


@@ -107,6 +172,14 @@ This changes the C<-m> option so that mounts are done read-only
 Enable very verbose messages.  This is particularly useful if you find
 a bug.
 
 Enable very verbose messages.  This is particularly useful if you find
 a bug.
 

+=item B<-V> | B<--version>
+
+Display the guestfish / libguestfs version number and exit.
+
+=item B<-x>
+
+Echo each command before executing it.
+

 =back
 
 =head1 COMMANDS ON COMMAND LINE
 =back
 
 =head1 COMMANDS ON COMMAND LINE


@@ -177,6 +250,33 @@ a space-separated list, enclosed in quotes.  For example:
 
  vgcreate VG "/dev/sda1 /dev/sdb1"
 
 
  vgcreate VG "/dev/sda1 /dev/sdb1"
 

+=head1 WILDCARDS AND GLOBBING
+
+Neither guestfish nor the underlying guestfs API performs
+wildcard expansion (globbing) by default.  So for example the
+following will not do what you expect:
+
+ rm-rf /home/*
+
+Assuming you don't have a directory literally called C</home/*>
+then the above command will return an error.
+
+To perform wildcard expansion, use the C<glob> command.
+
+ glob rm-rf /home/*
+
+runs C<rm-rf> on each path that matches (ie. potentially running
+the command many times), equivalent to:
+
+ rm-rf /home/jim
+ rm-rf /home/joe
+ rm-rf /home/mary
+
+C<glob> only works on simple guest paths and not on device names.
+
+If you have several parameters, each containing a wildcard, then glob
+will perform a cartesian product.
+

 =head1 COMMENTS
 
 Any line which starts with a I<#> character is treated as a comment
 =head1 COMMENTS
 
 Any line which starts with a I<#> character is treated as a comment


@@ -202,6 +302,46 @@ will create a directory C<local> on the host, and then export
 the contents of C</remote> on the mounted filesystem to
 C<local/remote-data.tar.gz>.  (See C<tgz-out>).
 
 the contents of C</remote> on the mounted filesystem to
 C<local/remote-data.tar.gz>.  (See C<tgz-out>).
 

+=head1 PIPES
+
+Use C<command E<lt>spaceE<gt> | command> to pipe the output of the
+first command (a guestfish command) to the second command (any host
+command).  For example:
+
+ cat /etc/passwd | awk -F: '$3 == 0 { print }'
+
+(where C<cat> is the guestfish cat command, but C<awk> is the host awk
+program).  The above command would list all accounts in the guest
+filesystem which have UID 0, ie. root accounts including backdoors.
+Other examples:
+
+ hexdump /bin/ls | head
+ list-devices | tail -1
+
+The space before the pipe symbol is required, any space after the pipe
+symbol is optional.  Everything after the pipe symbol is just passed
+straight to the host shell, so it can contain redirections, globs and
+anything else that makes sense on the host side.
+
+To use a literal argument which begins with a pipe symbol, you have
+to quote it, eg:
+
+ echo "|"
+
+=head1 HOME DIRECTORIES
+
+If a parameter starts with the character C<~> then the tilde may be
+expanded as a home directory path (either C<~> for the current user's
+home directory, or C<~user> for another user).
+
+Note that home directory expansion happens for users known I<on the
+host>, not in the guest filesystem.
+
+To use a literal argument which begins with a tilde, you have to quote
+it, eg:
+
+ echo "~"
+

 =head1 EXIT ON ERROR BEHAVIOUR
 
 By default, guestfish will ignore any errors when in interactive mode
 =head1 EXIT ON ERROR BEHAVIOUR
 
 By default, guestfish will ignore any errors when in interactive mode


@@ -213,19 +353,62 @@ If you prefix a command with a I<-> character, then that command will
 not cause guestfish to exit, even if that (one) command returns an
 error.
 
 not cause guestfish to exit, even if that (one) command returns an
 error.
 

-=head1 COMMANDS
+=head1 REMOTE CONTROL GUESTFISH OVER A SOCKET

 
 

-=head2 help
+Guestfish can be remote-controlled over a socket.  This is useful
+particularly in shell scripts where you want to make several different
+changes to a filesystem, but you don't want the overhead of starting
+up a guestfish process each time.

 
 

- help
- help cmd
+Start a guestfish server process using:

 
 

-Without any parameter, this lists all commands.  With a C<cmd>
-parameter, this displays detailed help for a command.
+ eval `guestfish --listen`

 
 

-=head2 quit | exit
+and then send it commands by doing:

 
 

-This exits guestfish.  You can also use C<^D> key.
+ guestfish --remote cmd [...]
+
+To cause the server to exit, send it the exit command:
+
+ guestfish --remote exit
+
+Note that the server will normally exit if there is an error in a
+command.  You can change this in the usual way.  See section I<EXIT ON
+ERROR BEHAVIOUR>.
+
+=head2 CONTROLLING MULTIPLE GUESTFISH PROCESSES
+
+The C<eval> statement sets the environment variable C<$GUESTFISH_PID>,
+which is how the C<--remote> option knows where to send the commands.
+You can have several guestfish listener processes running using:
+
+ eval `guestfish --listen`
+ pid1=$GUESTFISH_PID
+ eval `guestfish --listen`
+ pid2=$GUESTFISH_PID
+ ...
+ guestfish --remote=$pid1 cmd
+ guestfish --remote=$pid2 cmd
+
+=head2 STANDARD OUTPUT DURING REMOTE CONTROL
+
+Because of limitations in the C<eval> statement, stdout from the
+listener is currently redirected to C</dev/null>.
+
+Stderr is unchanged.
+
+=head2 REMOTE CONTROL DETAILS
+
+Remote control happens over a Unix domain socket called
+C</tmp/.guestfish-$UID/socket-$PID>, where C<$UID> is the effective
+user ID of the process, and C<$PID> is the process ID of the server.
+
+Guestfish client and server versions must match exactly.
+
+=head1 GUESTFISH COMMANDS
+
+The commands in this section are guestfish convenience commands, in
+other words, they are not part of the L<guestfs(3)> API.

 
 =head2 alloc | allocate
 
 
 =head2 alloc | allocate
 


@@ -278,6 +461,23 @@ editors.
 NOTE: This will not work reliably for large files
 (> 2 MB) or binary files containing \0 bytes.
 
 NOTE: This will not work reliably for large files
 (> 2 MB) or binary files containing \0 bytes.
 

+=head2 glob
+
+ glob command args...
+
+Expand wildcards in any paths in the args list, and run C<command>
+repeatedly on each matching path.
+
+See section WILDCARDS AND GLOBBING.
+
+=head2 help
+
+ help
+ help cmd
+
+Without any parameter, this lists all commands.  With a C<cmd>
+parameter, this displays detailed help for a command.
+

 =head2 lcd
 
  lcd directory
 =head2 lcd
 
  lcd directory


@@ -287,17 +487,79 @@ itself.
 
 Note that C<!cd> won't do what you might expect.
 
 
 Note that C<!cd> won't do what you might expect.
 

+=head2 more | less
+
+ more filename
+
+ less filename
+
+This is used to view a file.
+
+The default viewer is C<$PAGER>.  However if you use the alternate
+command C<less> you will get the C<less> command specifically.
+
+NOTE: This will not work reliably for large files
+(> 2 MB) or binary files containing \0 bytes.
+
+=head2 quit | exit
+
+This exits guestfish.  You can also use C<^D> key.
+
+=head2 reopen
+
+ reopen
+
+Close and reopen the libguestfs handle.  It is not necessary to use
+this normally, because the handle is closed properly when guestfish
+exits.  However this is occasionally useful for testing.
+
+=head2 time
+
+ time command args...
+
+Run the command as usual, but print the elapsed time afterwards.  This
+can be useful for benchmarking operations.
+
+=head1 COMMANDS
+

 @ACTIONS@
 
 =head1 ENVIRONMENT VARIABLES
 
 =over 4
 
 @ACTIONS@
 
 =head1 ENVIRONMENT VARIABLES
 
 =over 4
 

+=item EDITOR
+
+The C<edit> command uses C<$EDITOR> as the editor.  If not
+set, it uses C<vi>.
+
+=item GUESTFISH_PID
+
+Used with the I<--remote> option to specify the remote guestfish
+process to control.  See section I<REMOTE CONTROL GUESTFISH OVER A
+SOCKET>.
+
+=item HOME
+
+If compiled with GNU readline support, then the command history
+is saved in C<$HOME/.guestfish>
+
+=item LIBGUESTFS_APPEND
+
+Pass additional options to the guest kernel.
+

 =item LIBGUESTFS_DEBUG
 
 Set C<LIBGUESTFS_DEBUG=1> to enable verbose messages.  This has the
 same effect as using the B<-v> option.
 
 =item LIBGUESTFS_DEBUG
 
 Set C<LIBGUESTFS_DEBUG=1> to enable verbose messages.  This has the
 same effect as using the B<-v> option.
 

+=item LIBGUESTFS_MEMSIZE
+
+Set the memory allocated to the qemu process, in megabytes.  For
+example:
+
+ LIBGUESTFS_MEMSIZE=700
+

 =item LIBGUESTFS_PATH
 
 Set the path that guestfish uses to search for kernel and initrd.img.
 =item LIBGUESTFS_PATH
 
 Set the path that guestfish uses to search for kernel and initrd.img.


@@ -309,19 +571,10 @@ Set the default qemu binary that libguestfs uses.  If not set, then
 the qemu which was found at compile time by the configure script is
 used.
 
 the qemu which was found at compile time by the configure script is
 used.
 

-=item LIBGUESTFS_APPEND
-
-Pass additional options to the guest kernel.
+=item PAGER

 
 

-=item HOME
-
-If compiled with GNU readline support, then the command history
-is saved in C<$HOME/.guestfish>
-
-=item EDITOR
-
-The C<edit> command uses C<$EDITOR> as the editor.  If not
-set, it uses C<vi>.
+The C<more> command uses C<$PAGER> as the pager.  If not
+set, it uses C<more>.

 
 =back
 
 
 =back