Bug 682912

Summary:	wget -O truncates the output file before attempting the download.
Product:	Red Hat Enterprise Linux 5	Reporter:	Guil Barros <gbarros>
Component:	wget	Assignee:	Karsten Hopp <karsten>
Status:	CLOSED NOTABUG	QA Contact:	BaseOS QE - Apps <qe-baseos-apps>
Severity:	medium	Docs Contact:
Priority:	unspecified
Version:	5.6
Target Milestone:	rc
Target Release:	---
Hardware:	Unspecified
OS:	Unspecified
Whiteboard:
Fixed In Version:		Doc Type:	Bug Fix
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2011-03-08 12:44:12 UTC	Type:	---
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:

Description Guil Barros 2011-03-07 23:21:12 UTC

Description of problem:
# wget -O /etc/resolv.conf "http://people.redhat.com/gbarros/blah"
will truncate the output file before doing the dns lookup, thus failing and trashing the file.

open("/etc/resolv.conf", O_WRONLY|O_CREAT|O_TRUNC|O_LARGEFILE, 0666) = 3


Version-Release number of selected component (if applicable):
wget-1.11.4-2.el5_4.1.x86_64

How reproducible:
every time

Steps to Reproduce:
1. wget -O /etc/resolv.conf "http://people.redhat.com/gbarros/blah"
  
Actual results:
-O file gets clobbered

Expected results:
File is downloaded to a temporary location and moved into place when the download is complete.

Comment 1 Karsten Hopp 2011-03-08 12:44:12 UTC

That's expected and documented behaviour, this is from the man page:

Use of -O is not intended to mean simply "use the name file instead of the one in the URL;" rather, it is analogous to shell redirection: wget -O file http://foo is intended to work like wget -O - http://foo > file; file will be truncated immediately, and all downloaded content will be written there.