X-Git-Url: https://mattmccutchen.net/rsync/rsync.git/blobdiff_plain/aef2b8ce4124db39f715d38c7ade329005645e0d..75a1a04847beb40a6fb1ce684562c358843a56fb:/rsync.yo

diff --git a/rsync.yo b/rsync.yo
index 0ad14f39..c09114eb 100644
--- a/rsync.yo
+++ b/rsync.yo
@@ -781,7 +781,9 @@ quote(itemization(
   it() The file's data will be in an inconsistent state during the transfer
   and will be left that way if the transfer is interrupted or if an update
   fails.
-  it() A file that does not have write permissions cannot be updated.
+  it() A file that rsync cannot write to cannot be updated. While a super user
+  can update any file, a normal user needs to be granted write permission for
+  the open of the file for writing to be successful.
   it() The efficiency of rsync's delta-transfer algorithm may be reduced if
   some data in the destination file is overwritten before it can be copied to
   a position later in the file.  This does not apply if you use bf(--backup),
@@ -794,7 +796,8 @@ accessed by others, so be careful when choosing to use this for a copy.
 
 This option is useful for transferring large files with block-based changes
 or appended data, and also on systems that are disk bound, not network
-bound.
+bound.  It can also help keep a copy-on-write filesystem snapshot from
+diverging the entire contents of a file that only has minor changes.
 
 The option implies bf(--partial) (since an interrupted transfer does not delete
 the file), but conflicts with bf(--partial-dir) and bf(--delay-updates).
@@ -940,13 +943,14 @@ destination exactly matches that on the source.  Cases in which the
 destination may end up with extra hard links include the following:
 
 quote(itemization(
-  it() If the destination already contains hard links, rsync will not break
-  them explicitly.  However, if one or more of the paths have content
-  differences, the normal file-update process will break those links, unless
-  you are using the bf(--inplace) option.
+  it() If the destination contains extraneous hard-linked files, rsync will not
+  break them explicitly.  However, if one or more of the paths have content
+  differences, the normal file-update process will break those extra links
+  (unless you are using the bf(--inplace) option).
   it() If you specify a bf(--link-dest) directory that contains hard links,
-  rsync may use the same bf(--link-dest) file multiple times via several of
-  its paths.
+  the linking of the destination files against the bf(--link-dest) files can
+  cause some paths in the destination to become linked together due to the
+  bf(--link-dest) associations.
 ))
 
 Note that rsync can only detect hard links between files that are inside
@@ -960,7 +964,10 @@ see the bf(--inplace) option for more caveats).
 If incremental recursion is active (see bf(--recursive)), rsync may transfer
 a missing hard-linked file before it finds that another link for that contents
 exists elsewhere in the hierarchy.  This does not affect the accuracy of
-the transfer, just its efficiency.  One way to avoid this is to disable
+the transfer (i.e. which files are hard-linked together), just its efficiency
+(i.e. copying the data for a new, early copy of a hard-linked file that could
+have been found later in the transfer in another member of the hard-linked
+set of files).  One way to avoid this inefficiency is to disable
 incremental recursion using the bf(--no-inc-recursive) option.
 
 dit(bf(-p, --perms)) This option causes the receiving rsync to set the
@@ -1170,10 +1177,6 @@ dit(bf(-S, --sparse)) Try to handle sparse files efficiently so they take
 up less space on the destination.  Conflicts with bf(--inplace) because it's
 not possible to overwrite data in a sparse fashion.
 
-NOTE: Don't use this option when the destination is a Solaris "tmpfs"
-filesystem. It seems to have problems seeking over null regions,
-and ends up corrupting the files.
-
 dit(bf(-n, --dry-run)) This makes rsync perform a trial run that doesn't
 make any changes (and produces mostly the same output as a real run).  It
 is most commonly used in combination with the bf(-v, --verbose) and/or
@@ -1483,7 +1486,7 @@ initial items are marked as perishable -- see the FILTER RULES section):
 
 quote(quote(tt(RCS SCCS CVS CVS.adm RCSLOG cvslog.* tags TAGS .make.state
 .nse_depinfo *~ #* .#* ,* _$* *$ *.old *.bak *.BAK *.orig *.rej .del-*
-*.a *.olb *.o *.obj *.so *.exe *.Z *.elc *.ln core .svn/ .git/ .bzr/)))
+*.a *.olb *.o *.obj *.so *.exe *.Z *.elc *.ln core .svn/ .git/ .hg/ .bzr/)))
 
 then, files listed in a $HOME/.cvsignore are added to the list and any
 files listed in the CVSIGNORE environment variable (all cvsignore names
@@ -1613,6 +1616,12 @@ bf(--files-from) filenames are being sent from one host to another, the
 filenames will be translated from the sending host's charset to the
 receiving host's charset.
 
+NOTE: sorting the list of files in the --files-from input helps rsync to be
+more efficient, as it will avoid re-visiting the path elements that are shared
+between adjacent entries.  If the input is not sorted, some path elements
+(implied directories) may end up being scanned multiple times, and rsync will
+eventually unduplicate them after they get turned into file-list elements.
+
 dit(bf(-0, --from0)) This tells rsync that the rules/filenames it reads from a
 file are terminated by a null ('\0') character, not a NL, CR, or CR+LF.
 This affects bf(--exclude-from), bf(--include-from), bf(--files-from), and any