1 files changed, 28 insertions, 0 deletions
diff --git a/src/fe-text/term-terminfo.c b/src/fe-text/term-terminfo.c
index 4d5ca65b..68947f0c 100644
--- a/src/fe-text/term-terminfo.c
+++ b/src/fe-text/term-terminfo.c
@@ -765,3 +765,31 @@ void term_gets(GArray *buffer, int *line_count)
 		}
 	}
 }
+
+static const char* term_env_warning =
+	"You seem to be running Irssi inside %2$s, but the TERM environment variable "
+	"is set to '%1$s', which can cause display glitches.\n"
+	"Consider changing TERM to '%2$s' or '%2$s-256color' instead.";
+
+void term_environment_check(void)
+{
+	const char *term, *sty, *tmux, *multiplexer;
+
+	term = g_getenv("TERM");
+	sty = g_getenv("STY");
+	tmux = g_getenv("TMUX");
+
+	multiplexer = (sty && *sty) ? "screen" :
+	              (tmux && *tmux) ? "tmux" : NULL;
+
+	if (!multiplexer) {
+		return;
+	}
+
+	if (term && (g_str_has_prefix(term, "screen") ||
+	             g_str_has_prefix(term, "tmux"))) {
+		return;
+	}
+
+	g_warning(term_env_warning, term, multiplexer);
+}