How to open .img file

redhat828 · 07-29-2012, 12:03 AM

Hello Everybody,
How to see the content of .img file (initrd.img)and how to open this file?

John VV · 07-29-2012, 01:37 AM

initrd.img

good thing you clarified this a bit
The *.img 's i am used to are photos from the "Planetary Data System "

a fairly generic guide
-- for the Android phone , but....
http://android-dls.com/wiki/index.ph...ck_Boot_Images

as to your need ????
What operating system is this for?
the icon under your name "is MS Windows7 "

vonbiber · 07-29-2012, 02:06 AM

sometimes initrd.img is a compressed file (generally gzipped) and
the uncompressed file could be a cpio archive or a (an ext2) filesystem
To find out the type, run this command

Code:

file initrd.img

if it's a gzipped file, run

Code:

zcat initrd.img > /tmp/initrd.img

then run

Code:

file /tmp/initrd.img

If it's a cpio archive you can extract it with cpio, if it's
an ext2 filesystem you need to mount it (with the option -o loop)
You'll probably to run this as root
1st case, it's a cpio archive, then

Code:

mkdir /tmp/initrd_img
cd /tmp/initrd_img
zcat <path_to_your_initrd.img> | cpio -iumdv

Here, you should repace <path_to_your_initrd.img> by the path to your file
(e.g., if it's in your home directory, it could be ~/initrd.img)

In the second case, you just run (as root) on the uncompressed file

Code:

mkdir -p /mnt/tmp
mount -o loop initrd.img /mnt/tmp

heinblöd · 07-29-2012, 12:28 PM

A initrd.img is usually an "initial ramdisk" which is used during the boot of your computer, if the kernel is missing the modules (drivers) needed for your hardware.

You would create it after compiling a new Kernel and it's modules with

Code:

mkinitrd

Here is the man page http://linux.die.net/man/8/mkinitrd

Quote:

mkinitrd - creates initial ramdisk images for preloading modules

PTrenholme · 07-29-2012, 02:02 PM

Here's a script I once wrote to decompress InitRD files. It might work for you. By default, if the InitRD is in /boot, the script will create a sub-directory of /boot with the name of the InitRD file you unpacked as its name, and the contents of the image file inside that directory. The script will not execute if you are not running with an effective user id or zero (i.e., root).

Code:

#!/bin/bash
############################################################################################
#
# Decompress initial ram disk image files
#
# Arguments: [ directory [ output ]]
#
# Where directory is the location of the InitRD files (default: /boot)
# and   output    is the sub-directory of "directory" where
#                 the unpacked files should be stored.
#
# Note: Each image file will be unpacked into a sub-directory of "output" named with
#       the name of the image file being unpacked.
#
###########################################################################################
#
# Make sure we're running as root
if [ $(id -u) -ne 0 ]
then
  echo "FATAL: This program requires root access. Aborting." >/dev/stderr
  exit 1
fi
# Set the defaults
boot="/boot"            # Boot directory
dir="Initial_RAM_Disk"  # Subdirectory of $boot into which the scripts should be decompresed
# Are there any arguments?
if [ $# -gt 0 ]
then
  if [ -d "${1}" ]
  then
    boot="${1}"
  else
    echo \"$1\" is not a valid directory name.
    exit 1
  fi
fi
if [ x"$(pwd)" != x"$boot" ]
then
  echo cd ${boot}
  cd ${boot}
fi
# Is an output directory specified?
if [ $# -gt 1 ]
then
  if [ -d "${2}" ]
  then
    dir="${2}"
  else
    echo \"$2\" is not a valid directory name.
    exit 1
  fi
fi
# Create the output directory if it doesn't exist
[ -d "${dir}" ] || sudo mkdir "${dir}"
# Go to the output directory
cd "${dir}"
# Get the InitRD image file to be used
echo Enter the number corresponding to the image file you want expanded
select img in $(ls -1 ../*.img*) quit
do
  if [ ${img} == "quit" ]
  then
     break
  else
    out=$(basename ${img})
    echo "out="${out}
    echo "img="${img}
    mkdir -p "${out}"
    cd "${out}"
    gunzip -c "../${img}" | sudo cpio -idmv
    cd ../
  fi
done

jefro · 07-29-2012, 03:32 PM

I think everyone is right about what could be done but we still need to know more about this intrid.img file. What does the OP think it should be or where did he get it from?

I too think he was talking about a initial disk, generally compressed but we almost never tend to call it an .img file.

John VV · 07-29-2012, 06:21 PM

from the OP's other post about red hat rpms and yum
and the red hat icon under the name in that post
http://www.linuxquestions.org/questi...ry-4175419230/

but from this and that post ?????
Who knows ,seeing as there is very little in the way of usable information in the two .