Set PATH=/usr/sbin:/usr/bin:/sbin:/bin when running dpkg

This avoids a lot of problems from local installations of
scripting languages and other stuff in /usr/local for which
maintainer scripts are not prepared.

[v3: Inherit PATH during tests, check overrides work]
[v2: Add testing]

2 files changed, 11 insertions, 0 deletions

diff --git a/doc/apt.conf.5.xml b/doc/apt.conf.5.xml
index 64a26bc4a..ffbcba5a4 100644
--- a/doc/apt.conf.5.xml
+++ b/doc/apt.conf.5.xml
@@ -776,6 +776,13 @@ APT::Compressor::rev {
      using the list notation and each list item is passed as a single argument
      to &dpkg;.</para></listitem>
      </varlistentry>
+
+     <varlistentry><term><option>Path</option></term>
+     <listitem><para>This is a string that defines the <envar>PATH</envar>
+     environment variable used when running dpkg. It may be set to any
+     valid value of that environment variable; or the empty string, in
+     which case the variable is not changed.</para></listitem>
+     </varlistentry>
      
      <varlistentry><term><option>Pre-Invoke</option></term><term><option>Post-Invoke</option></term>
      <listitem><para>This is a list of shell commands to run before/after invoking &dpkg;. 
diff --git a/doc/examples/configure-index b/doc/examples/configure-index
index 99aedfd19..d7bd3daba 100644
--- a/doc/examples/configure-index
+++ b/doc/examples/configure-index
@@ -461,6 +461,10 @@ DPkg
    // Probably don't want to use force-downgrade..
    Options {"--force-overwrite";"--force-downgrade";}
 
+   // Defaults to /usr/sbin:/usr/bin:/sbin:/bin, might be set to empty
+   // string to inherit from environment
+   Path "<STRING>";
+
    // Auto re-mounting of a readonly /usr
    Pre-Invoke {"mount -o remount,rw /usr";};
    Post-Invoke {"mount -o remount,ro /usr";};