diff --git a/src/include/config.h b/src/include/config.h
index a5904c8..e9f334b 100644
--- a/src/include/config.h
+++ b/src/include/config.h
@@ -5,5 +5,8 @@
 #define AUTOESCAPE_CHAR '\\'
 #define NOMINIFY_CHAR '&'
 #define SEPARATOR_CHAR ','
+#define SHELL_CHAR '$'
+
+#define ALLOW_SHELL
 
 #define MAX_INCLUDE_DEPTH 10
diff --git a/src/parse.c b/src/parse.c
index b93935e..8dd949c 100644
--- a/src/parse.c
+++ b/src/parse.c
@@ -1,3 +1,9 @@
+#include <config.h>
+
+#ifdef ALLOW_SHELL
+#define _POSIX_C_SOURCE 2
+#endif
+
 #include <ctype.h>
 #include <stdlib.h>
 #include <string.h>
@@ -6,8 +12,6 @@
 #include <vector.h>
 #include <strings.h>
 
-#include <config.h>
-
 struct var {
 	struct string *var;
 	struct string *value;
@@ -128,6 +132,26 @@ autoescapeend:
 					fputc(data->data[i], out);
 				}
 				break;
+#ifdef ALLOW_SHELL
+			case SHELL_CHAR: {
+				FILE *process;
+				long start;
+				start = ++i;
+				while (data->data[i] != ESCAPE_CHAR)
+					++i;
+				data->data[i] = '\0';
+				process = popen(data->data + start, "r");
+				for (;;) {
+					int c;
+					c = fgetc(process);
+					if (c == EOF)
+						break;
+					mputc(&s, c, out);
+				}
+				pclose(process);
+				break;
+			}
+#endif
 			}
 		}
 		else
@@ -165,6 +189,7 @@ static int expandfile(struct expandfile *ret, char *filename, int level) {
 					goto error;
 				break;
 			case VAR_CHAR: case AUTOESCAPE_CHAR: case NOMINIFY_CHAR:
+			case SHELL_CHAR:
 				if (appendchar(ret->data, ESCAPE_CHAR))
 					goto error;
 				for (;;) {