CHANGES:
Version 8.0: New options for capacitor, cbreaker, diode, inductor, lswitch, Mux,
  resistor, rotbox, transformer.  New macros addtaps, binary_, Demux, Header,
  HeaderPin, hex_digit, hexadecimal_, Pr_xy, Pr_xz, Pr_yz, SQUID, KelvinR,
  FTcap, tconn, and tapped.
  Tweaked setrgb for svg output.  Generalized setview in lib3D.
Version 7.9: Added accessibility features to the documentation.
  Replaced Autologic with Autologix to allow multiple outputs and
  simplified expressions.  New macros savem4dir, restorem4dir. Options for
  vperp and Vperp.  Bug fix in source macro. Tweaked stacksplit_. Removed
  a name clash between libcct and liblog.
Version 7.8: Logic gate options for arbitrary negated inputs; lg_pin options.
  New macro FlipFlopX for simplicity and generality; new macros Cintersect,
  LCintersect, LCtangent, stacksplit_; modified Loopover_.
Version 7.7: SVG macro tweaks. Tweaked BOX_gate and bugfix in IOdefs in
  liblog.m4.
Version 7.6: New macro NPDT; new option for contact and relay; Autologic
  tweaks. Changed the Point_ simplification to require specific activation
  because of rare interaction with dpic loops.
Version 7.5: Usage has been simplified by making the initialization macros
  cct_init, gen_init, log_init, darrow_init, and threeD_init read the
  appropriate libraries automatically. New macros: jack, plug, tstrip,
  ccoax, pconnex, basename_, Autologic and associated wrappers for
  automatic Boolean functions, stack macros stackexec_, stackcopy_,
  stackprint_, stackreverse_. Simplified setting of drawing direction
  in composite macros. Bugfix in calls to BUFFER_gen.  Tweaked Point_
  for simpler output for common arguments. Reordered the arguments of
  round for consistency.
Version 7.4: New macro lthick. Simplified shadebox. The ifroff macro renamed
  to iftpic. New configuration file m4defaults.m4. Reworked darrow library
  for consistency with solid lines and arrows; new macro darc and wrappers
  Darc, Darrow, Dline; old version included in olddarrow.m4 to ease transition.
  Macros and examples fixed and made more robust for gpic (where possible).
Version 7.3: Options for sinusoid. Bug fix for switch(,,D). Heater macro.
  Modified Loopover_
Version 7.2: Tweaked crossover macro. Size options for inductor, resistor,
  capacitor; dlabel alignment options; new options for source, capacitor.
Version 7.1: Eliminated the HOMELIB_ macro for easier package installation
  and use (requires m4 -I <path> or the M4PATH environment variable).
Version 7.0: New options and wrapper macro scr for thyristor. Generalized
  ifinstr. Macros corner, round, resized. Options for mosfet. Tweaked
  b_current and color macros. Simplified \psbezier workaround assuming
  recent PSTricks.
Version 6.9: New workaround for \psbezier. Fixed round_. Default
  postprocessor reset to gpic. Style parameters for em_arrows.  Tweaks to
  winding, dimension_, fitcurve, distance. New macro rot_.
Version 6.8: New configuration file svg.m4 and other changes to support
  dpic svg output. Inkscape-aware changes. Opamp option. New macros
  ptrans and tgate. Tweaks to switch macros, color, variable, centerline,
  intersect_, inductor(,W), inductor(,L).
Version 6.7: Fixed source(,S) and ttmotor to work correctly with labels.
  Simplified several 2-terminal macros by using the reversed macro.
Version 6.6: New macros memristor, centerline.  Revised PSTricks patch.
  Options in mosfet, capacitor.  Opamp .C defined. Tweaks to avoid
  potential name conflicts. Fix for dashline.
Version 6.5: New macros Loopover_, m4xpand, showbox_, gyrator, norator,
  nullator, nterm, rotellipse, rotbox. Logic gate examples.
  Customization arguments for non-2-terminal elements.  Signal
  flow-graph macros tuned to allow large nodes; bug fix in sfgarc.  A
  patch for PSTricks to work around the context dependency of \psbezier
  within \pscustom.
Version 6.4: New macros Equidist3, f_box, rs_box, Darlington, View3D.
  Options for diode, inductor, transformer, consource.  Moved arrowhead
  initialization in pstricks.m4 and libcct.m4 for for more flexibility
  with diagrams embedded in latex files.
Version 6.3: New options for mosfet, diode, earphone. Better color support.
  Fixed system-dependent OR_gate problems. New macro cintersect.
Version 6.2: Replaced scr with a variant of thyristor. Bug fix in
  bi_trans. Options for source.
Version 6.1: New macros ttmotor, thyristor. Options for source, bi_trans,
  transformer.  More robust arcd, arcr.
Version 6.0: TikZ PGF compatibility.  Added transformer labels, optional
  FlipFlop labels. New macros dswitch, winding.  Tweaked nport, source,
  bi_trans, AND_gen, OR_gen, sinusoid, resistor.
Version 5.9: Simplified internal flags for pic processor and postprocessor.
  New antenna, cbreaker, dturn, and lbox macros.  Several changes to
  allow sprintf string arguments.  New options for buzzer, capacitor,
  dimension_, ebox, fuse, mosfet, source, and switch.  Fix of drjust.
  Better compatibility with pic macros.  Numerous changes to documentation.
Version 5.8: Simplified installation. Revised and augmented logic-gate library.
  Cleaner libgen macro output.  Improved b_current, bi_trans, ground, dtee.
  Dline and darrow corrected for gpic. New macros dashline, m4xtract.
Version 5.7: Psfrag examples.  Improved dline.  Added option and label in
  igbt.  Bug fix in tr_xy.  Multiple-emitter option in bi_trans.
Version 5.6: Better MetaPost, PDFLaTeX, and xfig support.  PDF examples.
  Reworked diode for easier customization and more options.  Improved
  shade, sfgline, dline, darrow, gap, point_, Point_, opamp, bi_trans,
  variable, em_arrows, larrow, rarrow, FlipFlop6.  New speaker, bell,
  microphone, buzzer.  Negated logic gate inputs and IEEE box logic gates.
Version 5.5: New macros potentiometer, variable, igbt, tline. Optional
  negated logic gate inputs. Options for diode, source.
Version 5.4: New Mux, for_, arca.  Reworked gate macros FlipFlop, AND_gate,
  OR_gate, NOT_gate.  Improved lg_pintxt, boxdim, s_box, s_ht, s_wd,
  s_dp, nport, resistor, opamp.  Completely reworked bi_tr, mosfet;
  deleted smosfet.  Minor additions and changes to the manual.
Version 5.3: New macros arcr, arcd, beginshade, endshade, larrow, rarrow,
  s_sp, s_ht, s_wd, Max, Min, sfgself.  Improved ground, sfgnode, diode,
  resistor.
Version 5.2: New macros arrowline, nport, vlength, boxcoord, reversed.
  Improved s_box, sfg_init, cross, fitcurve, sinusoid, transformer, darrow,
  mosfet, psset_, battery, diode, capacitor.
Version 5.1: Signal-flow graph (directed graph) macros.  More consistent
  rot3Dz.  Work-around for a bug in some pic processors invoked by the
  battery macro and for an arc instability invoked by the fuse macro.
  Modified ground, dimension_, par_, label macros, b_current, diode,
  transformer.  New macros gpar_, ujt, scr, contact, relay.
  Document fixes and additions.  Changes to examples for portability.
Version 5.0: Macros fuse, lpop, sinc; dpic-only sinusoid and fitcurve macros.
  More robust mosfet, smosfet, b_current, bi_tr, j_fet, intersect_.
  Editorial changes to the manual. Examples in Xfig version 3.2 format.
  Web-based examples and updated links.
Version 4.9: More robust NOT_gate.  Function pmod(), macro shade().  Tweaks
  to diode, dend, crossover. Newer manual and web references.  Binary
  tree and flowchart macros.
Version 4.8: More robust ebox, source, shadebox, gap.  Modified d_fet and
  e_fet.  Macros mosfet and smosfet.  More examples in the manual.  Bug
  fixes in Fector, transformer, BUFFER_gate and in sum_, abs_, neg_, sign_ (!).
Version 4.7: Fixed the excess-space bug in boxdims.sty.  Added Macros s_box,
  s_init, scale changes to make the package more metric-friendly.  Reworked
  amp, integrator, opamp, diode, battery and a few other macros for robustness
  and clarity.  Minor document changes.
Version 4.6: Percent-signs at the end of pstricks-generated lines.
  Index in the manual.  New copyright notices.
Version 4.5: Options for several 2-terminal macros.  Minor bug fixes and
  better robustness.  Documents edited for friendlier PC installation and use.
Version 4.3: Macros pt__ and boxdim.  Additions to the manual.  More robust
  dimension_, tuned FlipFlop for xfig.  PC installation information.
Version 4.2: Friendlier manual.  New Xfig prototype file to allow correct
  scaling.  Cleaned up b_current, added line_leng.  Changes and additions
  to logic gates.
Version 4.1: Xfig prototype file included.  Minor document changes.  Fixed
  recursive call bug and blank line bug.  Changed argument for dend
  macro.  Better arrowheads in circuit elements.
Version 4: Simplified library use.  Added capabilities and flexibility to
  several devices, added _init macros, modified b_current.  Updated
  font.m4, cosmetic changes to inductor.  Made gamp, amp, opamp,
  integrator more robust.  Deleted edel_ macro.  Fixed elen_ bug in
  darrow.m4.  Removed Capacitor, Inductor and others in favour of
  parameterized macros.  Iron-core inductors.  Re-worked use of arcs in
  basic elements for better robustness.  Edited examples document and
  the manual.
Version 3: Document changes, minor changes to dimension_, switch,
  ground, battery.  Added flexibility for several elements.  New
  diodes, Capacitor, transistors, hop, transformer.  Experimental
  Metafont version of basic elements.
Version 2.2: Replaced definitions of two-terminal elements
  with current arrow by an arrow-labelling macro.
Version 2.1: one or two examples simplified, and logic gates added.
Version 2:  considerable added flexibility and robustness,
  bug fixes, a few new constructs, a manual, and a complex logic-gate
  example.
