X-Git-Url: https://git.dogcows.com/gitweb?a=blobdiff_plain;ds=sidebyside;f=doc%2Ftar.texi;h=119ae168ed98f352103955fbe0097168352de172;hb=5a9ac8312e2336c854f6bec2d0ae404a3b3bc30d;hp=82c303d7024cea36a4f861cae48f0491ef499eb7;hpb=20ab569dc33b640354f862f584b9c964a367ac34;p=chaz%2Ftar

diff --git a/doc/tar.texi b/doc/tar.texi
index 82c303d..119ae16 100644
--- a/doc/tar.texi
+++ b/doc/tar.texi
@@ -4316,6 +4316,10 @@ Disable all warning messages.
 
 @subheading Keywords applicable for @command{tar --extract}
 @table @asis
+@kwindex existing-file
+@cindex @samp{%s: skipping existing file}, warning message
+@item existing-file
+@samp{%s: skipping existing file}
 @kwindex timestamp
 @cindex @samp{implausibly old time stamp %s}, warning message
 @cindex @samp{time stamp %s is %s s in the future}, warning message
@@ -9926,7 +9930,8 @@ will use the following default value:
 This keyword defines the value of the @samp{mtime} field that
 is written into the ustar header blocks for the extended headers.
 By default, the @samp{mtime} field is set to the modification time
-of the archive member described by that extended headers.
+of the archive member described by that extended header (or to the
+value of the @option{--mtime} option, if supplied).
 
 @item globexthdr.name=@var{string}
 This keyword allows user control over the name that is written into
@@ -10019,6 +10024,22 @@ same contents:
 --pax-option=exthdr.name=%d/PaxHeaders/%f,atime:=0
 @end smallexample
 
+@noindent
+If you extract files from such an archive and recreate the archive
+from them, you will also need to eliminate changes due to ctime, as
+shown in examples below:
+
+@smallexample
+--pax-option=exthdr.name=%d/PaxHeaders/%f,atime:=0,ctime:=0
+@end smallexample
+
+@noindent
+or
+
+@smallexample
+--pax-option=exthdr.name=%d/PaxHeaders/%f,atime:=0,delete=ctime
+@end smallexample
+
 @node Checksumming
 @subsection Checksumming Problems