X-Git-Url: https://git.brokenzipper.com/gitweb?a=blobdiff_plain;f=doc%2Ftar.texi;h=6a91f7642dd995ff731e6b9d14e7aec79d0ea879;hb=b0e8ba8839adae0872274d74739d60dd88cf16e6;hp=e27f5fcfe917cf107e131c83084528291913e810;hpb=b68057816b2f880a8bd2e9747a9b75d60f7e1a4f;p=chaz%2Ftar diff --git a/doc/tar.texi b/doc/tar.texi index e27f5fc..6a91f76 100644 --- a/doc/tar.texi +++ b/doc/tar.texi @@ -1802,6 +1802,7 @@ long form of the operation without affecting the performance. * extracting archives:: * extracting files:: * extract dir:: +* extracting untrusted archives:: * failing commands:: @end menu @@ -1922,6 +1923,23 @@ of the file names when you extract those files from the archive. @FIXME{IMPORTANT! show the final structure, here. figure out what it will be.} +@node extracting untrusted archives +@subsection Extracting Archives from Untrusted Sources + +Extracting files from archives can overwrite files that already exist. +If you receive an archive from an untrusted source, you should make a +new directory and extract into that directory, so that you don't have +to worry about the extraction overwriting one of your existing files. +For example, if @file{untrusted.tar} came from somewhere else on the +Internet, and you don't necessarily trust its contents, you can +extract it as follows: + +@example +$ @kbd{mkdir newdir} +$ @kbd{cd newdir} +$ @kbd{tar -xvf ../untrusted.tar} +@end example + @node failing commands @subsection Commands That Will Fail @@ -7775,11 +7793,7 @@ device, invocation. @end itemize -In previous versions of @acronym{GNU} @command{tar}, the -@samp{--compress-block} option (or even older: -@samp{--block-compress}) was necessary to reblock compressed archives. -It is now a dummy option just asking not to be used, and otherwise -ignored. If the output goes directly to a local disk, and not through +If the output goes directly to a local disk, and not through stdout, then the last write is not extended to a full record size. Otherwise, reblocking occurs. Here are a few other remarks on this topic: