From f81e7f815a6f36ff328f1b75319362166ae2e576 Mon Sep 17 00:00:00 2001
From: Lassi Kortela <lassi@lassi.io>
Date: Tue, 7 Apr 2020 10:21:45 +0300
Subject: [PATCH] Add os-executable-file builtin

---
 c/env.c       | 9 +++++++++
 c/libraries.c | 1 +
 c/scheme.h    | 1 +
 3 files changed, 11 insertions(+)

diff --git a/c/env.c b/c/env.c
index 8a964ba..b6ad0f3 100644
--- a/c/env.c
+++ b/c/env.c
@@ -277,3 +277,12 @@ value_t builtin_version_alist(value_t *args, uint32_t nargs)
     argcount("version-alist", nargs, 0);
     return get_version_alist();
 }
+
+value_t builtin_os_executable_file(value_t *args, uint32_t nargs)
+{
+    (void)args;
+    argcount("os-executable-file", nargs, 0);
+    char buf[512];
+    char *exe = get_exename(buf, sizeof(buf));
+    return exe ? string_from_cstr(exe) : FL_F;
+}
diff --git a/c/libraries.c b/c/libraries.c
index fa207c7..c02ab39 100644
--- a/c/libraries.c
+++ b/c/libraries.c
@@ -63,6 +63,7 @@ static struct builtin_procedure builtin_procedures[] = {
 
     { "features", builtin_features, R7RS_BASE | UP_2019 },
     { "version-alist", builtin_version_alist, SRFI_176 | UP_2019 },
+    { "os-executable-file", builtin_os_executable_file, UP_2019 },
 
     { "string?", fl_stringp, SRFI_13 | R7RS_BASE | UP_2019 },
     { "string-reverse", fl_string_reverse, SRFI_13 | UP_2019 },
diff --git a/c/scheme.h b/c/scheme.h
index 23901e5..d5ac53e 100644
--- a/c/scheme.h
+++ b/c/scheme.h
@@ -1010,6 +1010,7 @@ value_t envst_language_c(void);
 value_t get_version_alist(void);
 value_t builtin_features(value_t *args, uint32_t nargs);
 value_t builtin_version_alist(value_t *args, uint32_t nargs);
+value_t builtin_os_executable_file(value_t *args, uint32_t nargs);
 
 // env_*.c