fish: handle some out-of-memory conditions

[libguestfs.git] / guestfs-actions.pod

diff --git a/guestfs-actions.pod b/guestfs-actions.pod
index 039608d..5f66318 100644 (file)
--- a/guestfs-actions.pod
+++ b/guestfs-actions.pod
@@ -30,7 +30,8 @@ for whatever operations you want to perform (ie. read access if you
 just want to read the image or write access if you want to modify the
 image).
 
 just want to read the image or write access if you want to modify the
 image).
 

-This is equivalent to the qemu parameter C<-drive file=filename,cache=off>.
+This is equivalent to the qemu parameter
+C<-drive file=filename,cache=off,if=virtio>.

 
 Note that this call checks for the existence of C<filename>.  This
 stops you from specifying other types of drive which are supported
 
 Note that this call checks for the existence of C<filename>.  This
 stops you from specifying other types of drive which are supported


@@ -54,7 +55,7 @@ handle is closed.  We don't currently have any method to enable
 changes to be committed, although qemu can support this.
 
 This is equivalent to the qemu parameter
 changes to be committed, although qemu can support this.
 
 This is equivalent to the qemu parameter

-C<-drive file=filename,snapshot=on>.
+C<-drive file=filename,snapshot=on,if=virtio>.

 
 Note that this call checks for the existence of C<filename>.  This
 stops you from specifying other types of drive which are supported
 
 Note that this call checks for the existence of C<filename>.  This
 stops you from specifying other types of drive which are supported


@@ -885,6 +886,22 @@ C<device>.
 This function returns a string, or NULL on error.
 I<The caller must free the returned string after use>.
 
 This function returns a string, or NULL on error.
 I<The caller must free the returned string after use>.
 

+=head2 guestfs_get_memsize
+
+ int guestfs_get_memsize (guestfs_h *handle);
+
+This gets the memory size in megabytes allocated to the
+qemu subprocess.
+
+If C<guestfs_set_memsize> was not called
+on this handle, and if C<LIBGUESTFS_MEMSIZE> was not set,
+then this returns the compiled-in default value for memsize.
+
+For more information on the architecture of libguestfs,
+see L<guestfs(3)>.
+
+On error this function returns -1.
+

 =head2 guestfs_get_path
 
  const char *guestfs_get_path (guestfs_h *handle);
 =head2 guestfs_get_path
 
  const char *guestfs_get_path (guestfs_h *handle);


@@ -1012,6 +1029,25 @@ Because of the message protocol, there is a transfer limit
 of somewhere between 2MB and 4MB.  To transfer large files you should use
 FTP.
 
 of somewhere between 2MB and 4MB.  To transfer large files you should use
 FTP.
 

+=head2 guestfs_initrd_list
+
+ char **guestfs_initrd_list (guestfs_h *handle,
+               const char *path);
+
+This command lists out files contained in an initrd.
+
+The files are listed without any initial C</> character.  The
+files are listed in the order they appear (not necessarily
+alphabetical).  Directory names are listed as separate items.
+
+Old Linux kernels (2.4 and earlier) used a compressed ext2
+filesystem as initrd.  We I<only> support the newer initramfs
+format (compressed cpio files).
+
+This function returns a NULL-terminated array of strings
+(like L<environ(3)>), or NULL if there was an error.
+I<The caller must free the strings and the array after use>.
+

 =head2 guestfs_is_busy
 
  int guestfs_is_busy (guestfs_h *handle);
 =head2 guestfs_is_busy
 
  int guestfs_is_busy (guestfs_h *handle);


@@ -1300,6 +1336,18 @@ See also: L<mkdtemp(3)>
 This function returns a string, or NULL on error.
 I<The caller must free the returned string after use>.
 
 This function returns a string, or NULL on error.
 I<The caller must free the returned string after use>.
 

+=head2 guestfs_mkfifo
+
+ int guestfs_mkfifo (guestfs_h *handle,
+               int mode,
+               const char *path);
+
+This call creates a FIFO (named pipe) called C<path> with
+mode C<mode>.  It is just a convenient wrapper around
+C<guestfs_mknod>.
+
+This function returns 0 on success or -1 on error.
+

 =head2 guestfs_mkfs
 
  int guestfs_mkfs (guestfs_h *handle,
 =head2 guestfs_mkfs
 
  int guestfs_mkfs (guestfs_h *handle,


@@ -1312,6 +1360,81 @@ example C<ext3>.
 
 This function returns 0 on success or -1 on error.
 
 
 This function returns 0 on success or -1 on error.
 

+=head2 guestfs_mknod
+
+ int guestfs_mknod (guestfs_h *handle,
+               int mode,
+               int devmajor,
+               int devminor,
+               const char *path);
+
+This call creates block or character special devices, or
+named pipes (FIFOs).
+
+The C<mode> parameter should be the mode, using the standard
+constants.  C<devmajor> and C<devminor> are the
+device major and minor numbers, only used when creating block
+and character special devices.
+
+This function returns 0 on success or -1 on error.
+
+=head2 guestfs_mknod_b
+
+ int guestfs_mknod_b (guestfs_h *handle,
+               int mode,
+               int devmajor,
+               int devminor,
+               const char *path);
+
+This call creates a block device node called C<path> with
+mode C<mode> and device major/minor C<devmajor> and C<devminor>.
+It is just a convenient wrapper around C<guestfs_mknod>.
+
+This function returns 0 on success or -1 on error.
+
+=head2 guestfs_mknod_c
+
+ int guestfs_mknod_c (guestfs_h *handle,
+               int mode,
+               int devmajor,
+               int devminor,
+               const char *path);
+
+This call creates a char device node called C<path> with
+mode C<mode> and device major/minor C<devmajor> and C<devminor>.
+It is just a convenient wrapper around C<guestfs_mknod>.
+
+This function returns 0 on success or -1 on error.
+
+=head2 guestfs_mkswap
+
+ int guestfs_mkswap (guestfs_h *handle,
+               const char *device);
+
+Create a swap partition on C<device>.
+
+This function returns 0 on success or -1 on error.
+
+=head2 guestfs_mkswap_L
+
+ int guestfs_mkswap_L (guestfs_h *handle,
+               const char *label,
+               const char *device);
+
+Create a swap partition on C<device> with label C<label>.
+
+This function returns 0 on success or -1 on error.
+
+=head2 guestfs_mkswap_U
+
+ int guestfs_mkswap_U (guestfs_h *handle,
+               const char *uuid,
+               const char *device);
+
+Create a swap partition on C<device> with UUID C<uuid>.
+
+This function returns 0 on success or -1 on error.
+

 =head2 guestfs_mount
 
  int guestfs_mount (guestfs_h *handle,
 =head2 guestfs_mount
 
  int guestfs_mount (guestfs_h *handle,


@@ -1337,6 +1460,18 @@ call, in order to improve reliability.
 
 This function returns 0 on success or -1 on error.
 
 
 This function returns 0 on success or -1 on error.
 

+=head2 guestfs_mount_loop
+
+ int guestfs_mount_loop (guestfs_h *handle,
+               const char *file,
+               const char *mountpoint);
+
+This command lets you mount C<file> (a filesystem image
+in a file) on a mount point.  It is entirely equivalent to
+the command C<mount -o loop file mountpoint>.
+
+This function returns 0 on success or -1 on error.
+

 =head2 guestfs_mount_options
 
  int guestfs_mount_options (guestfs_h *handle,
 =head2 guestfs_mount_options
 
  int guestfs_mount_options (guestfs_h *handle,


@@ -1677,6 +1812,24 @@ to return the existing UUID of a filesystem.
 
 This function returns 0 on success or -1 on error.
 
 
 This function returns 0 on success or -1 on error.
 

+=head2 guestfs_set_memsize
+
+ int guestfs_set_memsize (guestfs_h *handle,
+               int memsize);
+
+This sets the memory size in megabytes allocated to the
+qemu subprocess.  This only has any effect if called before
+C<guestfs_launch>.
+
+You can also change this by setting the environment
+variable C<LIBGUESTFS_MEMSIZE> before the handle is
+created.
+
+For more information on the architecture of libguestfs,
+see L<guestfs(3)>.
+
+This function returns 0 on success or -1 on error.
+

 =head2 guestfs_set_path
 
  int guestfs_set_path (guestfs_h *handle,
 =head2 guestfs_set_path
 
  int guestfs_set_path (guestfs_h *handle,


@@ -2075,6 +2228,29 @@ The array of strings will always have length C<2n+1>, where
 C<n> keys and values alternate, followed by the trailing NULL entry.
 I<The caller must free the strings and the array after use>.
 
 C<n> keys and values alternate, followed by the trailing NULL entry.
 I<The caller must free the strings and the array after use>.
 

+=head2 guestfs_umask
+
+ int guestfs_umask (guestfs_h *handle,
+               int mask);
+
+This function sets the mask used for creating new files and
+device nodes to C<mask & 0777>.
+
+Typical umask values would be C<022> which creates new files
+with permissions like "-rw-r--r--" or "-rwxr-xr-x", and
+C<002> which creates new files with permissions like
+"-rw-rw-r--" or "-rwxrwxr-x".
+
+The default umask is C<022>.  This is important because it
+means that directories and device nodes will be created with
+C<0644> or C<0755> mode even if you specify C<0777>.
+
+See also L<umask(2)>, C<guestfs_mknod>, C<guestfs_mkdir>.
+
+This call returns the previous umask.
+
+On error this function returns -1.
+

 =head2 guestfs_umount
 
  int guestfs_umount (guestfs_h *handle,
 =head2 guestfs_umount
 
  int guestfs_umount (guestfs_h *handle,