+ # Define sed as an alias.
+ # It is not always possible to use aliases. Aliases are guaranteed to work
+ # if the executing shell is bash and either it is invoked as /bin/sh or
+ # is a version >= 2.0, supporting shopt. This is the common case.
+ # Two other approaches (use of a variable $sed or of a function func_sed
+ # instead of an alias) require massive, fragile code changes.
+ # An other approach (use of function sed) requires `which sed` - but 'which'
+ # is hard to emulate, due to missing "test -x" on some platforms.
+ if test -n "$BASH_VERSION"; then
+ shopt -s expand_aliases >/dev/null 2>&1
+ fi