handle environment variables more consistently

 * the registers beginning with "$" are exported into sub-process
   environments. Therefore macros can now modify the environment
   (variables) of commands executed via EC/EG.
   A variable can be modified temporarily, e.g.:
   [[$FOO] ^U[$FOO]bar$ EC...$ ][$FOO]
 * SciTECO accesses the global environment registers instead of
   using g_getenv(). Therefore now, tilde-expansion will always
   use the current value of the "$HOME" register.
   Previously, both register and environment variable could diverge.
 * This effectively fully maps the process environment to a subset of
   Q-Registers beginning with "$".
 * This hasn't been implemented by mapping those registers to
   special implementations that updates the process environment
   directly, since g_setenv() is non-thread-safe on UNIX
   and we're expected to have threads soon - at least in the GTK+ UI.

1 files changed, 14 insertions, 0 deletions

diff --git a/src/qregisters.h b/src/qregisters.h
index ec40bb4..0ca230e 100644
--- a/src/qregisters.h
+++ b/src/qregisters.h
@@ -255,6 +255,10 @@ public:
 	insert(QRegister *reg)
 	{
 		reg->must_undo = must_undo;
+		/* FIXME: Returns already existing regs with the same name.
+		   This could be used to optimize commands that initialize
+		   a register if it does not yet exist (saves one table
+		   lookup): */
 		RBTree::insert(reg);
 		return reg;
 	}
@@ -283,6 +287,13 @@ public:
 		return operator [](buf);
 	}
 
+	inline QRegister *
+	nfind(const gchar *name)
+	{
+		QRegister reg(name);
+		return (QRegister *)RBTree::nfind(&reg);
+	}
+
 	void edit(QRegister *reg);
 	inline QRegister *
 	edit(const gchar *name)
@@ -295,6 +306,9 @@ public:
 		return reg;
 	}
 
+	void set_environ(void);
+	gchar **get_environ(void);
+
 	void clear(void);
 };