exiftool
Use exiftool for metadata.
$ exiftool nineveh.png
ExifTool Version Number : 13.44
File Name : nineveh.png
Directory : .
File Size : 2.9 MB
File Modification Date/Time : 2026:02:17 03:54:45-05:00
File Access Date/Time : 2026:02:17 03:54:45-05:00
File Inode Change Date/Time : 2026:02:17 03:54:45-05:00
File Permissions : -rw-rw-r--
File Type : PNG
File Type Extension : png
MIME Type : image/png
Image Width : 1497
Image Height : 746
Bit Depth : 8
Color Type : RGB
Compression : Deflate/Inflate
Filter : Adaptive
Interlace : Noninterlaced
Significant Bits : 8 8 8
Software : Shutter
Warning : [minor] Trailer data after PNG IEND chunk
Image Size : 1497x746
Megapixels : 1.1
ltrace
to check the linked library calls.
matt@pandora:/$ ltrace /usr/bin/pandora_backup
[SNIP]
system("tar -cvf /root/.backup/pandora-b"...tar: /root/.backup/pandora-backup.tar.gz: Cannot open: Permission denied
tar: Error is not recoverable: exiting now