Comment 10 for bug 1622313

No, gparted does not work in this case (but in most other cases gparted is a good tool).

But you can mount the partition with the iso9660 file system manually, and after that you can look at it with a file manager, or as illustrated below, with command line tools. For example, I can read the file README.diskdefines in the iso9660 file system. Try it :-)

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sudodus@xenial32 ~ $ sudo lsblk -f /dev/sdd
[sudo] password for sudodus:
NAME FSTYPE LABEL UUID MOUNTPOINT
sdd iso9660 Lubuntu 16.04.1 LTS i386 2016-09-09-18-15-41-00
└─sdd1 iso9660 Lubuntu 16.04.1 LTS i386 2016-09-09-18-15-41-00
sudodus@xenial32 ~ $ sudo lsblk -m /dev/sdd
NAME SIZE OWNER GROUP MODE
sdd 3,7G root disk brw-rw----
└─sdd1 859M root disk brw-rw----
sudodus@xenial32 ~ $ sudo mount /dev/sdd1 /mnt
mount: /dev/sdd1 is write-protected, mounting read-only
sudodus@xenial32 ~ $ ls -l /mnt
totalt 36
dr-xr-xr-x 1 root root 2048 sep 9 20:15 boot
dr-xr-xr-x 1 root root 2048 sep 9 20:15 casper
dr-xr-xr-x 1 root root 2048 sep 9 20:15 dists
dr-xr-xr-x 1 root root 2048 sep 9 20:15 install
dr-xr-xr-x 1 root root 18432 sep 9 20:15 isolinux
-r--r--r-- 1 root root 3114 sep 9 20:15 md5sum.txt
dr-xr-xr-x 1 root root 2048 sep 9 20:15 pics
dr-xr-xr-x 1 root root 2048 sep 9 20:15 pool
dr-xr-xr-x 1 root root 2048 sep 9 20:15 preseed
-r--r--r-- 1 root root 227 sep 9 20:15 README.diskdefines
lr-xr-xr-x 1 root root 1 sep 9 20:15 ubuntu -> .
sudodus@xenial32 ~ $ cat /mnt/README.diskdefines
#define DISKNAME Lubuntu 16.04.1 LTS "Xenial Xerus" - Beta i386
#define TYPE binary
#define TYPEbinary 1
#define ARCH i386
#define ARCHi386 1
#define DISKNUM 1
#define DISKNUM1 1
#define TOTALNUM 0
#define TOTALNUM0 1
sudodus@xenial32 ~ $
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