diff --git a/src/blackhole.cc b/src/blackhole.cc
index 37f05ec..a60b462 100644
--- a/src/blackhole.cc
+++ b/src/blackhole.cc
@@ -6,6 +6,7 @@
 #include <climits>
 #include <cstdlib>
 #include <cstring>
+#include <filesystem>
 #include <initializer_list>
 #include <string>
 
@@ -13,7 +14,7 @@
 #include <sys/stat.h>
 #include <unistd.h>
 
-static bool is_writable_dir(const std::string &dir)
+static bool is_writable_dir(const std::filesystem::path &dir)
 {
     int old_errno = errno;
 
@@ -40,7 +41,7 @@ static bool is_writable_dir(const std::string &dir)
     return S_ISDIR(st.st_mode);
 }
 
-static std::string get_tmpdir(void)
+static std::filesystem::path get_tmpdir(void)
 {
     for (const char *tryenv : {"TMPDIR", "TMP", "TEMP", "TEMPDIR"}) {
         const char *tmpdir = getenv(tryenv);
@@ -62,15 +63,10 @@ static std::string get_tmpdir(void)
     if (is_writable_dir("/var/tmp"))
         return "/var/tmp";
 
-    int old_errno = errno;
-    char *workdir = get_current_dir_name();
-    errno = old_errno;
-    if (workdir != nullptr) {
-        std::string wdir_str(workdir);
-        free(workdir);
-        if (is_writable_dir(wdir_str))
-            return wdir_str;
-    }
+    std::string workdir = std::filesystem::current_path();
+
+    if (is_writable_dir(workdir))
+        return workdir;
 
     LOG(FATAL) << "Unable to get temporary directory.";
     std::abort();
@@ -91,9 +87,9 @@ BlackHole::BlackHole()
     : tmpdir(std::nullopt)
     , filepath(std::nullopt)
 {
-    static std::string tempdir = get_tmpdir();
+    static std::filesystem::path tempdir = get_tmpdir();
 
-    std::string bh_template = tempdir + "/ip2unix.XXXXXX";
+    std::string bh_template = tempdir / "ip2unix.XXXXXX";
 
     char *c_bh_template = strdup(bh_template.c_str());
 
diff --git a/src/rules/parse.cc b/src/rules/parse.cc
index 59c90db..e05d27e 100644
--- a/src/rules/parse.cc
+++ b/src/rules/parse.cc
@@ -5,6 +5,7 @@
 
 #include <algorithm>
 #include <cstddef>
+#include <filesystem>
 #include <iostream>
 #include <optional>
 #include <string>
@@ -323,14 +324,6 @@ static void print_arg_error(size_t rulepos, const std::string &arg, size_t pos,
                   << ' ' << msg << std::endl;
 }
 
-std::string make_absolute(const std::string &path)
-{
-    if (path.empty() || path[0] == '/')
-        return path;
-
-    return std::string(get_current_dir_name()) + '/' + path;
-}
-
 std::optional<Rule> parse_rule_arg(size_t rulepos, const std::string &arg)
 {
     std::string buf;
@@ -346,7 +339,7 @@ std::optional<Rule> parse_rule_arg(size_t rulepos, const std::string &arg)
             if (i == arglen || arg[i] == ',') {
                 /* Handle key=value options. */
                 if (key.value() == "path") {
-                    rule.socket_path = make_absolute(buf);
+                    rule.socket_path = std::filesystem::absolute(buf);
 #ifdef SYSTEMD_SUPPORT
                 } else if (key.value() == "systemd") {
                     rule.socket_activation = true;