X-Git-Url: http://git.annexia.org/?p=libguestfs.git;a=blobdiff_plain;f=perl%2Flib%2FSys%2FGuestfs.pm;h=001fa8800890e1512cef606413eab07073e5b813;hp=3f00394bfc47bbdbb424c4cea33d865799f49eb0;hb=45d78361d791f4a752fca9472b81bdc75f9f92a4;hpb=e118c14b9552de311cbc1734e03a3226b484c1e8

diff --git a/perl/lib/Sys/Guestfs.pm b/perl/lib/Sys/Guestfs.pm
index 3f00394..001fa88 100644
--- a/perl/lib/Sys/Guestfs.pm
+++ b/perl/lib/Sys/Guestfs.pm
@@ -405,6 +405,13 @@ The first element is the name of the program to run.
 Subsequent elements are parameters.  The list must be
 non-empty (ie. must contain a program name).
 
+The return value is anything printed to I<stdout> by
+the command.
+
+If the command returns a non-zero exit status, then
+this function returns an error message.  The error message
+string is the content of I<stderr> from the command.
+
 The C<$PATH> environment variable will contain at least
 C</usr/bin> and C</bin>.  If you require a program from
 another location, you should provide the full path in the
@@ -416,11 +423,19 @@ correct places.  It is the caller's responsibility to ensure
 all filesystems that are needed are mounted at the right
 locations.
 
+Because of the message protocol, there is a transfer limit 
+of somewhere between 2MB and 4MB.  To transfer large files you should use
+FTP.
+
 =item @lines = $h->command_lines (\@arguments);
 
 This is the same as C<$h-E<gt>command>, but splits the
 result into a list of lines.
 
+Because of the message protocol, there is a transfer limit 
+of somewhere between 2MB and 4MB.  To transfer large files you should use
+FTP.
+
 =item $h->config ($qemuparam, $qemuvalue);
 
 This can be used to add arbitrary qemu command line parameters
@@ -432,6 +447,16 @@ The first character of C<param> string must be a C<-> (dash).
 
 C<value> can be NULL.
 
+=item $h->cp ($src, $dest);
+
+This copies a file from C<src> to C<dest> where C<dest> is
+either a destination filename or destination directory.
+
+=item $h->cp_a ($src, $dest);
+
+This copies a file or directory from C<src> to C<dest>
+recursively using the C<cp -a> command.
+
 =item $result = $h->debug ($subcmd, \@extraargs);
 
 The C<$h-E<gt>debug> command exposes some internals of
@@ -442,6 +467,17 @@ There is no comprehensive help for this command.  You have
 to look at the file C<daemon/debug.c> in the libguestfs source
 to find out what you can do.
 
+=item $kmsgs = $h->dmesg ();
+
+This returns the kernel messages (C<dmesg> output) from
+the guest kernel.  This is sometimes useful for extended
+debugging of problems.
+
+Another way to get the same information is to enable
+verbose messages with C<$h-E<gt>set_verbose> or by setting
+the environment variable C<LIBGUESTFS_DEBUG=1> before
+running the program.
+
 =item $h->download ($remotefilename, $filename);
 
 Download file C<remotefilename> and save it as C<filename>
@@ -451,6 +487,33 @@ C<filename> can also be a named pipe.
 
 See also C<$h-E<gt>upload>, C<$h-E<gt>cat>.
 
+=item $h->drop_caches ($whattodrop);
+
+This instructs the guest kernel to drop its page cache,
+and/or dentries and inode caches.  The parameter C<whattodrop>
+tells the kernel what precisely to drop, see
+L<http://linux-mm.org/Drop_Caches>
+
+Setting C<whattodrop> to 3 should drop everything.
+
+This automatically calls L<sync(2)> before the operation,
+so that the maximum guest memory is freed.
+
+=item $h->end_busy ();
+
+This sets the state to C<READY>, or if in C<CONFIG> then it leaves the
+state as is.  This is only used when implementing
+actions using the low-level API.
+
+For more information on states, see L<guestfs(3)>.
+
+=item $equality = $h->equal ($file1, $file2);
+
+This compares the two files C<file1> and C<file2> and returns
+true if their content is exactly equal, or false otherwise.
+
+The external L<cmp(1)> program is used for the comparison.
+
 =item $existsflag = $h->exists ($path);
 
 This returns C<true> if and only if there is a file, directory
@@ -542,6 +605,15 @@ This returns the verbose messages flag.
 This command installs GRUB (the Grand Unified Bootloader) on
 C<device>, with the root directory being C<root>.
 
+=item $dump = $h->hexdump ($path);
+
+This runs C<hexdump -C> on the given C<path>.  The result is
+the human-readable, canonical hex dump of the file.
+
+Because of the message protocol, there is a transfer limit 
+of somewhere between 2MB and 4MB.  To transfer large files you should use
+FTP.
+
 =item $busy = $h->is_busy ();
 
 This returns true iff this handle is busy processing a command
@@ -688,7 +760,7 @@ as necessary.  This is like the C<mkdir -p> shell command.
 =item $h->mkfs ($fstype, $device);
 
 This creates a filesystem on C<device> (usually a partition
-of LVM logical volume).  The filesystem type is C<fstype>, for
+or LVM logical volume).  The filesystem type is C<fstype>, for
 example C<ext3>.
 
 =item $h->mount ($device, $mountpoint);
@@ -734,6 +806,18 @@ the list of devices (eg. C</dev/sda1>, C</dev/VG/LV>).
 
 Some internal mounts are not shown.
 
+=item $h->mv ($src, $dest);
+
+This moves a file from C<src> to C<dest> where C<dest> is
+either a destination filename or destination directory.
+
+=item $h->ping_daemon ();
+
+This is a test probe into the guestfs daemon running inside
+the qemu subprocess.  Calling this function checks that the
+daemon responds to the ping message, without affecting the daemon
+or attached block device(s) in any other way.
+
 =item $h->pvcreate ($device);
 
 This creates an LVM physical volume on the named C<device>,
@@ -906,6 +990,31 @@ C<path> should be a file or directory in the mounted file system
 
 This is the same as the C<statvfs(2)> system call.
 
+=item @stringsout = $h->strings ($path);
+
+This runs the L<strings(1)> command on a file and returns
+the list of printable strings found.
+
+Because of the message protocol, there is a transfer limit 
+of somewhere between 2MB and 4MB.  To transfer large files you should use
+FTP.
+
+=item @stringsout = $h->strings_e ($encoding, $path);
+
+This is like the C<$h-E<gt>strings> command, but allows you to
+specify the encoding.
+
+See the L<strings(1)> manpage for the full list of encodings.
+
+Commonly useful encodings are C<l> (lower case L) which will
+show strings inside Windows/x86 files.
+
+The returned strings are transcoded to UTF-8.
+
+Because of the message protocol, there is a transfer limit 
+of somewhere between 2MB and 4MB.  To transfer large files you should use
+FTP.
+
 =item $h->sync ();
 
 This syncs the disk, so that any writes are flushed through to the
@@ -1024,6 +1133,11 @@ As a special case, if C<size> is C<0>
 then the length is calculated using C<strlen> (so in this case
 the content cannot contain embedded ASCII NULs).
 
+I<NB.> Owing to a bug, writing content containing ASCII NUL
+characters does I<not> work, even if the length is specified.
+We hope to resolve this bug in a future version.  In the meantime
+use C<$h-E<gt>upload>.
+
 Because of the message protocol, there is a transfer limit 
 of somewhere between 2MB and 4MB.  To transfer large files you should use
 FTP.