Great. We are moving forward, albeit slowly:
~/Desktop/patch/libX11-1.1.99.2$ sudo dpkg-buildpackage
dpkg-buildpackage: set CFLAGS to default value: -g -O2
dpkg-buildpackage: set CPPFLAGS to default value:
dpkg-buildpackage: set LDFLAGS to default value: -Wl,-Bsymbolic-functions
dpkg-buildpackage: set FFLAGS to default value: -g -O2
dpkg-buildpackage: set CXXFLAGS to default value: -g -O2
dpkg-buildpackage: source package libx11
dpkg-buildpackage: source version 2:1.1.99.2-1ubuntu2
dpkg-buildpackage: source changed by Bryce Harrington <bryce@ubuntu.com>
dpkg-buildpackage: host architecture amd64
debian/rules clean
Can't exec "debian/rules": Permission denied at /usr/bin/dpkg-buildpackage line 510.
dpkg-buildpackage: failure: debian/rules clean failed with unknown exit code -1