[Bug 1715481] [NEW] wget -N ignores file size differences

[Andrew]

Public bug reported:

The man page states:

"The time-stamping in GNU Wget is turned on using ‘--timestamping’
(‘-N’) option, or through timestamping = on directive in .wgetrc. With
this option, for each file it intends to download, Wget will check
whether a local file of the same name exists. If it does, and the remote
file is not newer, Wget will not download it.

If the local file does not exist, or the sizes of the files do not
match, Wget will download the remote file no matter what the time-stamps
say. "

Note the last sentence carefully:  "...the sizes of the files do not
match... no matter what the timestamps say."

To duplicate:
wget -N <remote file>
cp /dev/null <remote file that is now local>
wget -N <remote file>
~~~~~~~~~~~~~~~~~~~~~~~~
Note, it will state "HTTP request sent, awaiting response... 304 Not Modified
File ‘<remote file>’ not modified on server. Omitting download.

Obviously the sizes of the files do not match and it should download the
file.  You can also edit the file and manually delete (or add I suppose)
a few lines.

Not related, however I would like to also point out that if I change the
string "$1000" to "$4000" in a document on the remote, the size of the
file does not change, however the files and data are clearly different.
This case usage would break anything depending on actual changes.  Such
as automatically getting a vendor's price lists, not just changes to
what is essentially the outer envelope of the file. Kind of important,
no?

ProblemType: Bug
DistroRelease: Ubuntu 16.04
Package: wget 1.17.1-1ubuntu1.2
ProcVersionSignature: Ubuntu 4.4.0-93.116-generic 4.4.79
Uname: Linux 4.4.0-93-generic x86_64
ApportVersion: 2.20.1-0ubuntu2.10
Architecture: amd64
CurrentDesktop: Unity
Date: Wed Sep  6 12:42:20 2017
InstallationDate: Installed on 2016-09-11 (359 days ago)
InstallationMedia: Ubuntu 16.04.1 LTS "Xenial Xerus" - Release amd64 (20160719)
SourcePackage: wget
UpgradeStatus: No upgrade log present (probably fresh install)

** Affects: wget (Ubuntu)
     Importance: Undecided
         Status: New


** Tags: amd64 apport-bug xenial

-- 
You received this bug notification because you are a member of Ubuntu
Foundations Bugs, which is subscribed to wget in Ubuntu.
https://bugs.launchpad.net/bugs/1715481

Title:
  wget -N ignores file size differences

Status in wget package in Ubuntu:
  New

Bug description:
  The man page states:

  "The time-stamping in GNU Wget is turned on using ‘--timestamping’
  (‘-N’) option, or through timestamping = on directive in .wgetrc. With
  this option, for each file it intends to download, Wget will check
  whether a local file of the same name exists. If it does, and the
  remote file is not newer, Wget will not download it.

  If the local file does not exist, or the sizes of the files do not
  match, Wget will download the remote file no matter what the time-
  stamps say. "

  Note the last sentence carefully:  "...the sizes of the files do not
  match... no matter what the timestamps say."

  To duplicate:
  wget -N <remote file>
  cp /dev/null <remote file that is now local>
  wget -N <remote file>
  ~~~~~~~~~~~~~~~~~~~~~~~~
  Note, it will state "HTTP request sent, awaiting response... 304 Not Modified
  File ‘<remote file>’ not modified on server. Omitting download.

  Obviously the sizes of the files do not match and it should download
  the file.  You can also edit the file and manually delete (or add I
  suppose) a few lines.

  Not related, however I would like to also point out that if I change
  the string "$1000" to "$4000" in a document on the remote, the size of
  the file does not change, however the files and data are clearly
  different.  This case usage would break anything depending on actual
  changes.  Such as automatically getting a vendor's price lists, not
  just changes to what is essentially the outer envelope of the file.
  Kind of important, no?

  ProblemType: Bug
  DistroRelease: Ubuntu 16.04
  Package: wget 1.17.1-1ubuntu1.2
  ProcVersionSignature: Ubuntu 4.4.0-93.116-generic 4.4.79
  Uname: Linux 4.4.0-93-generic x86_64
  ApportVersion: 2.20.1-0ubuntu2.10
  Architecture: amd64
  CurrentDesktop: Unity
  Date: Wed Sep  6 12:42:20 2017
  InstallationDate: Installed on 2016-09-11 (359 days ago)
  InstallationMedia: Ubuntu 16.04.1 LTS "Xenial Xerus" - Release amd64 (20160719)
  SourcePackage: wget
  UpgradeStatus: No upgrade log present (probably fresh install)

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/wget/+bug/1715481/+subscriptions