diff --git a/src/action_cc.cc b/src/action_cc.cc
index 2344bbc..be8ef29 100644
--- a/src/action_cc.cc
+++ b/src/action_cc.cc
@@ -446,10 +446,10 @@ NM_ACTION_(nickel_misc) {
     } else if (!strcmp(arg, "force_usb_connection")) {
         // we could call libnickel directly, but I prefer not to
         FILE *nhs;
-        NM_CHECK(nullptr, (nhs = fopen("/tmp/nickel-hardware-status", "w")), "could not open nickel hardware status pipe: %s", strerror(errno));
+        NM_CHECK(nullptr, (nhs = fopen("/tmp/nickel-hardware-status", "w")), "could not open nickel hardware status pipe: %m");
 
         const char *msg = "usb plug add";
-        NM_CHECK(nullptr, fputs(msg, nhs) >= 0, "could not write message '%s' to pipe: %s", msg, strerror(errno));
+        NM_CHECK(nullptr, fputs(msg, nhs) >= 0, "could not write message '%s' to pipe: %m", msg);
 
         fclose(nhs);
     } else {
diff --git a/src/config.c b/src/config.c
index b40648c..307adea 100644
--- a/src/config.c
+++ b/src/config.c
@@ -51,7 +51,7 @@ nm_config_file_t *nm_config_files() {
 
     struct dirent **nl;
     int n = scandir(NM_CONFIG_DIR, &nl, nm_config_files_filter, alphasort);
-    NM_CHECK(NULL, n != -1, "could not scan config dir: %s", strerror(errno));
+    NM_CHECK(NULL, n != -1, "could not scan config dir: %m");
 
     for (int i = 0; i < n; i++) {
         struct dirent *de = nl[i];
@@ -240,7 +240,7 @@ nm_config_t *nm_config_parse(nm_config_file_t *files) {
         cfgfile = fopen(cf->path, "r");
 
         if (!cfgfile)
-            RETERR("could not open file: %s", strerror(errno));
+            RETERR("could not open file: %m");
 
         while ((line_sz = getline(&line, &line_bufsz, cfgfile)) != -1) {
             line_n++;
diff --git a/src/generator_c.c b/src/generator_c.c
index 6cf6911..7f751d4 100644
--- a/src/generator_c.c
+++ b/src/generator_c.c
@@ -91,7 +91,7 @@ NM_GENERATOR_(_test_time) {
 NM_GENERATOR_(kfmon) {
     struct stat sb;
     if (stat(KFMON_IPC_SOCKET, &sb))
-        NM_ERR_RET(NULL, "error checking '%s': stat: %s", KFMON_IPC_SOCKET, strerror(errno));
+        NM_ERR_RET(NULL, "error checking '%s': stat: %m", KFMON_IPC_SOCKET);
 
     if (time_in_out->tv_sec == sb.st_mtim.tv_sec && time_in_out->tv_nsec == sb.st_mtim.tv_nsec) {
         nm_err_set(NULL);