X-Git-Url: http://git.annexia.org/?p=libguestfs.git;a=blobdiff_plain;f=src%2Fguestfs.pod;h=915d8605a3759f94a7a0b854f1f7b9be03abecb9;hp=4e216f12743b1ce0c2db2c9fdc5b06c35fd2a3fa;hb=daf55c07978cd29fe6675911bf76da0b056fdae1;hpb=c0f96e9c6eda77e5e99de862dd4366010e4a1ab8 diff --git a/src/guestfs.pod b/src/guestfs.pod index 4e216f1..915d860 100644 --- a/src/guestfs.pod +++ b/src/guestfs.pod @@ -354,7 +354,7 @@ doing: guestfs_download (g, filename, "/dev/stdout"); -and you can write tar output to a pipe C by doing: +and you can write tar output to a file descriptor C by doing: char devfd[64]; snprintf (devfd, sizeof devfd, "/dev/fd/%d", fd); @@ -775,6 +775,9 @@ them. =item Autosync / forgetting to sync. +I Autosync is enabled by default for all API users starting +from libguestfs 1.5.24. This section only applies to older versions. + When modifying a filesystem from C or another language, you B unmount all filesystems and call L explicitly before you close the libguestfs handle. You can also call: @@ -793,9 +796,6 @@ Note that in L autosync is the default. So quick and dirty guestfish scripts that forget to sync will work just fine, which can make this very puzzling if you are trying to debug a problem. -Update: Autosync is enabled by default for all API users starting from -libguestfs 1.5.24. - =item Mount option C<-o sync> should not be the default. If you use L, then C<-o sync,noatime> are added @@ -1285,7 +1285,7 @@ Create a handle by calling L. Call L to free the handle and release all resources used. For information on using multiple handles and threads, see the section -L below. +L above. =head2 guestfs_create @@ -1293,15 +1293,16 @@ L below. Create a connection handle. -You have to call L (or one of the equivalent -calls) on the handle at least once. +On success this returns a non-NULL pointer to a handle. On error it +returns NULL. -This function returns a non-NULL pointer to a handle on success or -NULL on error. +You have to "configure" the handle after creating it. This includes +calling L (or one of the equivalent calls) on +the handle at least once. After configuring the handle, you have to call L. -You may also want to configure error handling for the handle. See +You may also want to configure error handling for the handle. See the L section below. =head2 guestfs_close @@ -1310,6 +1311,12 @@ L section below. This closes the connection handle and frees up all resources used. +If autosync was set on the handle and the handle was launched, then +this implicitly calls various functions to unmount filesystems and +sync the disk. See L for more details. + +If a close callback was set on the handle, then it is called. + =head1 ERROR HANDLING API functions can return errors. For example, almost all functions @@ -1665,7 +1672,8 @@ old functions C, C, C, C and C are no longer documented in this -manual page. +manual page. Because of the ABI guarantee, the old functions continue +to work. Handles generate events when certain things happen, such as log messages being generated, progress messages during long-running @@ -1954,12 +1962,13 @@ To attach a named piece of data, use the following call: C is the name to associate with this data, and C is an arbitrary pointer (which can be C). Any previous item with the -same name is overwritten. +same key is overwritten. -You can use any C you want, but names beginning with an -underscore character are reserved for internal libguestfs purposes -(for implementing language bindings). It is recommended to prefix the -name with some unique string to avoid collisions with other users. +You can use any C you want, but your key should I start with +an underscore character. Keys beginning with an underscore character +are reserved for internal libguestfs purposes (eg. for implementing +language bindings). It is recommended that you prefix the key with +some unique string to avoid collisions with other users. To retrieve the pointer, use: @@ -2662,6 +2671,10 @@ actions. L command and documentation. +=item C + +L command and documentation. + =item C C API example code. @@ -2810,6 +2823,15 @@ We have tested block devices up to 1 exabyte (2**60 or 1,152,921,504,606,846,976 bytes) using sparse files backed by an XFS host filesystem. +Although libguestfs probably does not impose any limit, the underlying +host storage will. If you store disk images on a host ext4 +filesystem, then the maximum size will be limited by the maximum ext4 +file size (currently 16 TB). If you store disk images as host logical +volumes then you are limited by the maximum size of an LV. + +For the hugest disk image files, we recommend using XFS on the host +for storage. + =head2 MAXIMUM SIZE OF A PARTITION The MBR (ie. classic MS-DOS) partitioning scheme uses 32 bit sector