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User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.0; en-US; rv:1.7.12) Gecko/20050915 Firefox/1.0.7

Description of problem:
When trying to create a new ramdisk, via mkinitrd manaully or when upgrading a kernel rpm, mkinitrd will fail if /dev/zero is not present.  The failure message given is very generic, and simply states that mkinitrd fails, and provides a return code of 1.  This would be nicer if the mkinitrd script verified the existance of /dev/zero and provided a useful error message if it was not there. 

Version-Release number of selected component (if applicable):
mkinitrd-3.5.13.6-1

How reproducible:
Always

Steps to Reproduce:
1.  Remove /dev/zero device
2.  Try run mkinitrd (or install a new kernel)
3.
  

Actual Results:  # Manual mkinitrd
[root@bunson root]# mkinitrd -f mytestimage.img 2.4.21-37.ELsmp
[root@bunson root]# echo $?
1
[root@bunson root]#
# Kernel installation
[root@bunson root]# rpm -ivh kernel-2.4.21-37.EL.i686.rpm
Preparing...                ########################################### [100%]
   1:kernel                 ########################################### [100%]
mkinitrd failed
[root@bunson root]#




Expected Results:  # Manual mkinitrd
[root@bunson root]# mkinitrd -f mytestimage.img 2.4.21-37.ELsmp
[root@bunson root]# echo $?
0
[root@bunson root]#
# Kernel installation
[root@bunson root]# rpm -ivh kernel-2.4.21-37.EL.i686.rpm
Preparing...                ########################################### [100%]
   1:kernel                 ########################################### [100%]
[root@bunson root]# echo $?
[root@bunson root]# 0

Additional info:

Here's a potential fix. 

25a26
> #     Michael Stahnke <mastahnke>
481c482,489
< dd if=/dev/zero of=$IMAGE bs=1k count=$IMAGESIZE 2> /dev/null || exit 1
---
>
> if [ -c /dev/zero ]; then
>    dd if=/dev/zero of=$IMAGE bs=1k count=$IMAGESIZE 2> /dev/null || exit 1
> else
>    echo "Error /dev/zero device required for mkinitrd." >&2
>    exit 1
> fi
>