[ILUG] apt-get: 'Build-dependencies for foo could not be satisfied'

[Justin Mason]

Hi apt wizards --

Does anyone know how to go about debugging this error? e.g.:

  : jm 46...; sudo apt-get build-dep ffmpeg
  Reading package lists... Done
  Building dependency tree... Done
  E: Build-dependencies for ffmpeg could not be satisfied.


That's all well and good -- but I'd like to figure out exactly where the
problem may lie, so I can *fix* it.  Google just finds a lot of people
reporting problems getting build-deps for various packages, similarly.


FWIW, my sources.list:

  # https://wiki.ubuntu.com/BreezyUpgradeNotes
  # https://wiki.ubuntu.com/Archive
  deb http://ftp.heanet.ie/pub/ubuntu dapper-updates main restricted universe multiverse
  deb-src http://ftp.heanet.ie/pub/ubuntu dapper-updates main restricted universe multiverse

  deb http://ftp.heanet.ie/pub/ubuntu dapper-security main restricted universe multiverse
  deb-src http://ftp.heanet.ie/pub/ubuntu dapper-security main restricted universe multiverse

  deb http://ftp.heanet.ie/pub/ubuntu dapper main universe multiverse restricted
  deb-src http://ftp.heanet.ie/pub/ubuntu dapper main universe multiverse restricted

  deb http://archive.canonical.com/ubuntu dapper-commercial main


looks like it should be fine in my opinion.


: jm 70...; sudo ls -la /etc/apt/*
-rw------- 1 root root     0 Jan 12  2005 /etc/apt/secring.gpg
-rw-r--r-- 1 root root   954 Aug  3 11:33 /etc/apt/sources.list
-rw------- 1 root root  1200 Jan 18  2006 /etc/apt/trustdb.gpg
-rw-r--r-- 1 root root 23129 Jan 18  2006 /etc/apt/trusted.gpg
-rw-r--r-- 1 root root 23129 Jan 18  2006 /etc/apt/trusted.gpg~

/etc/apt/apt.conf.d:
total 28
drwxr-xr-x 2 root root 4096 Jun  8 10:53 .
drwxr-xr-x 4 root root 4096 Aug  3 11:34 ..
-rw-r--r-- 1 root root   80 Apr  3 15:44 05aptitude
-rw-r--r-- 1 root root  129 May 26 14:35 15adept-periodic-update
-rw-r--r-- 1 root root   85 Mar 23  2005 20archive
-rw-r--r-- 1 root root  227 May 29 07:34 50unattended-upgrades
-rw-r--r-- 1 root root  116 Oct 10  2005 99update-notifier

/etc/apt/sources.list.d:
total 8
drwxr-xr-x 2 root root 4096 Apr 18 20:47 .
drwxr-xr-x 4 root root 4096 Aug  3 11:34 ..


any tips?

--j.