allow specifying the number of columns

3 files changed, 33 insertions, 10 deletions

diff --git a/optcvt.sh b/optcvt.sh
index 2f3f89c..b73c095 100755
--- a/optcvt.sh
+++ b/optcvt.sh
@@ -8,6 +8,8 @@ COLUMNS="${SIZE#* }"
 
 if test "$COLUMNS" -ge $((2*$MINWIDTH+1)); then
 	exec $TCVT "$@"
+elif test -z "$@"; then
+	exec "$SHELL"
 else
 	exec "$@"
 fi
diff --git a/tcvt.1 b/tcvt.1
index 80bb803..dd0e272 100644
--- a/tcvt.1
+++ b/tcvt.1
@@ -4,7 +4,7 @@
 tcvt - two column virtual terminal
 .Sh SYNOPSIS
 .nf
-\fBtcvt\fP \fIprogram options\fP
+\fBtcvt\fP \fItcvt options\fP \fIprogram options\fP
 .PP
 \fBoptcvt\fP \fIprogram options\fP
 .fi
@@ -13,11 +13,25 @@ The two column virtual terminal emulates a virtual terminal inside another virtu
 The emulated virtual terminal is twice as tall and half as wide as the original terminal.
 The upper half of the virtual terminal goes to the left and the lower half goes to the right of the original terminal.
 An \fBANSI\fP terminal is emulated.
-Neither program takes any options.
-All arguments are forwarded to the called program.
 
-While \fBtcvt\fP splits does this conversion unconditionally, the \fBoptcvt\fP can be used with smaller terminals.
+While \fBtcvt\fP does this conversion unconditionally, the \fBoptcvt\fP can be used with smaller terminals.
 It will only invoke \fBtcvt\fP, if the terminal is wide enough and otherwise simply exec the passed program.
+.Sh OPTIONS
+Both programs take a program and options to that program.
+They execute the given program.
+If no program is given a shell is executed.
+
+In addition the \fBtcvt\fP tool accepts a few switches.
+.Bl -tag -width indent
+.It Fl c , Fl Fl columns
+Specify the number of columns. This defaults to two.
+.It Fl h , Fl Fl help
+Print a quick option overview and exit.
+.It Fl Fl
+Signal end of options.
+.El
+
+Any non-option argument signals the end of options for \fBtcvt\fP.
 .Sh BUGS
 Not all \fBANSI\fP terminal features are emulated.
 If you experience rendering issues, you can export the environment variable \fBTCVT_DEVEL\fP.
diff --git a/tcvt.py b/tcvt.py
index 590b111..4393cfb 100755
--- a/tcvt.py
+++ b/tcvt.py
@@ -39,6 +39,7 @@ import struct
 import curses
 import errno
 import time
+import optparse
 
 def init_color_pairs():
     for bi, bc in enumerate((curses.COLOR_BLACK, curses.COLOR_RED,
@@ -292,7 +293,7 @@ def compose_dicts(dct1, dct2):
     return result
 
 class Terminal:
-    def __init__(self, acsc):
+    def __init__(self, acsc, columns):
         self.mode = (self.feed_simple,)
         self.realscreen = None
         self.screen = None
@@ -300,12 +301,13 @@ class Terminal:
         self.graphics_font = False
         self.graphics_chars = acsc # really initialized after
         self.lastchar = ord(b' ')
+        self.columns = columns
 
     def switchmode(self):
         if isinstance(self.screen, Columns):
             self.screen = Simple(self.realscreen)
         else:
-            self.screen = Columns(self.realscreen)
+            self.screen = Columns(self.realscreen, self.columns)
         self.screen.refresh()
 
     def resized(self):
@@ -327,7 +329,7 @@ class Terminal:
         self.realscreen.keypad(1)
         curses.start_color()
         init_color_pairs()
-        self.screen = Columns(self.realscreen)
+        self.screen = Columns(self.realscreen, self.columns)
         curses.noecho()
         curses.raw()
         self.graphics_chars = compose_dicts(self.graphics_chars, acs_map())
@@ -535,8 +537,13 @@ def set_cloexec(fd):
     fcntl.fcntl(fd, fcntl.F_SETFD, flags)
 
 def main():
+    parser = optparse.OptionParser()
+    parser.disable_interspersed_args()
+    parser.add_option("-c", "--columns", dest="columns", metavar="N",
+                      type="int", default=2, help="number of columns")
+    options, args = parser.parse_args()
     keymapping, acsc = compute_keymap(symbolic_keymapping)
-    t = Terminal(acsc)
+    t = Terminal(acsc, options.columns)
 
     errpiper, errpipew = os.pipe()
     set_cloexec(errpipew)
@@ -545,10 +552,10 @@ def main():
         os.close(errpiper)
         os.environ["TERM"] = "ansi"
         try:
-            if len(sys.argv) < 2:
+            if len(args) < 1:
                 os.execvp(os.environ["SHELL"], [os.environ["SHELL"]])
             else:
-                os.execvp(sys.argv[1], sys.argv[1:])
+                os.execvp(args[0], args)
         except OSError as err:
             os.write(errpipew, "exec failed: %s" % (err,))
         sys.exit(1)