=encoding utf8 =head1 NAME virt-cat - Display files in a virtual machine =head1 SYNOPSIS virt-cat [--options] -d domname file [file ...] virt-cat [--options] -a disk.img [-a disk.img ...] file [file ...] Old-style: virt-cat domname file virt-cat disk.img file =head1 DESCRIPTION C is a command line tool to display the contents of C where C exists in the named virtual machine (or disk image). Multiple filenames can be given, in which case they are concatenated together. Each filename must be a full path, starting at the root directory (starting with '/'). C can be used to quickly view a file. To edit a file, use C. For more complex cases you should look at the L tool. =head1 EXAMPLES Display C file from inside the libvirt VM called C: virt-cat -d mydomain /etc/fstab List syslog messages from a VM disk image file: virt-cat -a disk.img /var/log/messages | tail Find out what DHCP IP address a VM acquired: virt-cat -d mydomain /var/log/messages | \ grep 'dhclient: bound to' | tail Find out what packages were recently installed: virt-cat -d mydomain /var/log/yum.log | tail Find out who is logged on inside a virtual machine: virt-cat -d mydomain /var/run/utmp > /tmp/utmp who /tmp/utmp or who was logged on: virt-cat -d mydomain /var/log/wtmp > /tmp/wtmp last -f /tmp/wtmp =head1 OPTIONS =over 4 =item B<--help> Display brief help. =item B<-a> file =item B<--add> file Add I which should be a disk image from a virtual machine. If the virtual machine has multiple block devices, you must supply all of them with separate I<-a> options. The format of the disk image is auto-detected. To override this and force a particular format use the I<--format=..> option. =item B<-c> URI =item B<--connect> URI If using libvirt, connect to the given I. If omitted, then we connect to the default libvirt hypervisor. If you specify guest block devices directly (I<-a>), then libvirt is not used at all. =item B<-d> guest =item B<--domain> guest Add all the disks from the named libvirt guest. =item B<--echo-keys> When prompting for keys and passphrases, virt-cat normally turns echoing off so you cannot see what you are typing. If you are not worried about Tempest attacks and there is no one else in the room you can specify this flag to see what you are typing. =item B<--format=raw|qcow2|..> | B<--format> The default for the I<-a> option is to auto-detect the format of the disk image. Using this forces the disk format for I<-a> options which follow on the command line. Using I<--format> with no argument switches back to auto-detection for subsequent I<-a> options. For example: virt-cat --format=raw -a disk.img forces raw format (no auto-detection) for C. virt-cat --format=raw -a disk.img --format -a another.img forces raw format (no auto-detection) for C and reverts to auto-detection for C. If you have untrusted raw-format guest disk images, you should use this option to specify the disk format. This avoids a possible security problem with malicious guests (CVE-2010-3851). See also L. =item B<--keys-from-stdin> Read key or passphrase parameters from stdin. The default is to try to read passphrases from the user by opening C. =item B<-v> =item B<--verbose> Enable verbose messages for debugging. =item B<-V> =item B<--version> Display version number and exit. =item B<-x> Enable tracing of libguestfs API calls. =back =head1 OLD-STYLE COMMAND LINE ARGUMENTS Previous versions of virt-cat allowed you to write either: virt-cat disk.img [disk.img ...] file or virt-cat guestname file whereas in this version you should use I<-a> or I<-d> respectively to avoid the confusing case where a disk image might have the same name as a guest. For compatibility the old style is still supported. =head1 SHELL QUOTING Libvirt guest names can contain arbitrary characters, some of which have meaning to the shell such as C<#> and space. You may need to quote or escape these characters on the command line. See the shell manual page L for details. =head1 SEE ALSO L, L, L, L. =head1 AUTHOR Richard W.M. Jones L =head1 COPYRIGHT Copyright (C) 2010 Red Hat Inc. This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.