Merge branch 'master' of https://github.com/gcalderone/Gnuplot.jl

docs/src/terminals.md

@@ -28,7 +28,31 @@ Press the `h` key on the window to display an help message with all available ke
 ## Plot in a terminal application (`dumb`, `sixel` and `sixelgd`)
 Gnuplot supports plotting in a terminal application, with no need for X11 or other GUI support, via the `dumb`, `sixel` and `sixelgd` terminals.  These are extremely useful when you run Julia on a remote shell through `ssh`, with no X11 forwarding.
 
-The `dumb` terminal uses ASCII characters to draw a plot, while `sixel` and `sixelgd` actually use bitmaps (but require Sixel support to be enabled in the terminal, e.g. `xterm -ti vt340`).  A sixel plot on `xterm` looks as follows:
+The `dumb` terminal uses ASCII characters to draw a plot, while `sixel` and `sixelgd` actually use bitmaps (but require Sixel support to be enabled in the terminal, e.g. `xterm -ti vt340`).  Dumb terminal can be used as follows:
+
+```jldoctest; setup = :(using Gnuplot; origterm = Gnuplot.options.term)
+julia> Gnuplot.options.term = "dumb size 60,15";
+
+julia> @gp "plot sin(x)"
+
+    1 +-------------------------------------------------+
+  0.8 |-+         *+ *         + ** **      +    *  * +-|
+  0.6 |-+        *   **          *   *   sin(x) *******-|
+  0.4 |*+        *    *         *     *         *    *+-|
+  0.2 |*+       *      *        *     *        *      *-|
+    0 |*+       *      *       *       *       *      *-|
+      | *      *       *       *       *      *        *|
+ -0.2 |-*      *        *     *        *      *       +*|
+ -0.4 |-+*    *         *     *         *    *        +*|
+ -0.6 |-+*    *          *   *          **   *        +-|
+ -0.8 |-+ *  *     +     ** ** +         *  *         +-|
+   -1 +-------------------------------------------------+
+     -10          -5           0            5           10
+
+julia> Gnuplot.options.term = origterm;
+
+```
+A sixel plot on `xterm` looks as follows:
 ![](assets/sixelgd.png)
 
 The above terminals are available if gnuplot has been compiled with the `--with-bitmap-terminals` option enabled and Libgd (only for `sixelgd`).

src/Gnuplot.jl

@@ -520,6 +520,18 @@ function readTask(gp::GPSession)
     delete!(sessions, gp.sid)
 end
 
+# Read data from `from` and forward them to `stdout`.
+#
+# This is similar to `Base.write(to::IO, from::IO)` when called as
+# write(stdout, from), but the difference is in situation when
+# `stdout` changes. This function writes data to the changed `stdout`,
+# whereas the call to `Base.write` writes to the original `stdout`
+# forever.
+function writeToStdout(from::IO)
+    while !eof(from)
+        write(stdout, readavailable(from))
+    end
+end
 
 function GPSession(sid::Symbol)
     session = DrySession(sid)
@@ -535,13 +547,16 @@ function GPSession(sid::Symbol)
     end
 
     pin  = Base.Pipe()
+    pout = Base.Pipe()
     perr = Base.Pipe()
-    proc = run(pipeline(`$(options.cmd)`, stdin=pin, stdout=stdout, stderr=perr), wait=false)
+    proc = run(pipeline(`$(options.cmd)`, stdin=pin, stdout=pout, stderr=perr), wait=false)
     chan = Channel{String}(32)
 
     # Close unused sides of the pipes
+    Base.close(pout.in)
     Base.close(perr.in)
     Base.close(pin.out)
+    Base.start_reading(pout.out)
     Base.start_reading(perr.out)
 
     out = GPSession(getfield.(Ref(session), fieldnames(DrySession))...,
@@ -550,6 +565,7 @@ function GPSession(sid::Symbol)
 
     # Start reading tasks
     @async readTask(out)
+    @async writeToStdout(pout)
 
     # Read gnuplot default terminal
     if options.term == ""