diff --git a/Makefile.in b/Makefile.in
index 48fdbd2..7ecb325 100644
--- a/Makefile.in
+++ b/Makefile.in
@@ -57,7 +57,7 @@ SOURCES=$(wildcard *.c)
 OBJS=$(subst .c,.o,$(SOURCES))
 TESTS=$(patsubst %.c,%,$(wildcard test/*.c))
 
-SHOBJS=pseudo_tables.o pseudo_util.o
+SHOBJS=pseudo_tables.o pseudo_util.o strtol.o
 DBOBJS=pseudo_db.o
 WRAPOBJS=pseudo_wrappers.o
 
@@ -100,15 +100,15 @@ $(BIN) $(LIB):
 
 pseudo: $(PSEUDO)
 
-$(PSEUDO): pseudo.o $(SHOBJS) $(DBOBJS) pseudo_client.o pseudo_server.o pseudo_ipc.o | $(BIN)
+$(PSEUDO): pseudo.o $(SHOBJS) $(DBOBJS) pseudo_client.o pseudo_client_scanf.o pseudo_server.o pseudo_ipc.o | $(BIN)
 	$(CC) $(CFLAGS) $(CFLAGS_PSEUDO) -o $(PSEUDO) \
-		pseudo.o pseudo_server.o pseudo_client.o pseudo_ipc.o \
+		pseudo.o pseudo_server.o pseudo_client.o pseudo_client_scanf.o pseudo_ipc.o \
 		$(DBOBJS) $(SHOBJS) $(LDFLAGS) $(DB_LDFLAGS) $(CLIENT_LDFLAGS)
 
 pseudolog: $(PSEUDOLOG)
 
-$(PSEUDOLOG): pseudolog.o $(SHOBJS) $(DBOBJS) pseudo_client.o pseudo_ipc.o | $(BIN)
-	$(CC) $(CFLAGS) $(CFLAGS_PSEUDO) -o $(PSEUDOLOG) pseudolog.o pseudo_client.o pseudo_ipc.o \
+$(PSEUDOLOG): pseudolog.o $(SHOBJS) $(DBOBJS) pseudo_client.o pseudo_client_scanf.o pseudo_ipc.o | $(BIN)
+	$(CC) $(CFLAGS) $(CFLAGS_PSEUDO) -o $(PSEUDOLOG) pseudolog.o pseudo_client.o pseudo_client_scanf.o pseudo_ipc.o \
 		$(DBOBJS) $(SHOBJS) $(LDFLAGS) $(DB_LDFLAGS) $(CLIENT_LDFLAGS)
 
 pseudodb: $(PSEUDODB)
@@ -119,9 +119,9 @@ $(PSEUDODB): pseudodb.o $(SHOBJS) $(DBOBJS) pseudo_ipc.o | $(BIN)
 
 libpseudo: $(LIBPSEUDO)
 
-$(LIBPSEUDO): $(WRAPOBJS) pseudo_client.o pseudo_ipc.o $(SHOBJS) | $(LIB)
+$(LIBPSEUDO): $(WRAPOBJS) pseudo_client.o pseudo_client_scanf.o pseudo_ipc.o $(SHOBJS) | $(LIB)
 	$(CC) $(CFLAGS) $(CFLAGS_PSEUDO) -shared -o $(LIBPSEUDO) \
-		pseudo_client.o pseudo_ipc.o \
+		pseudo_client.o pseudo_client_scanf.o pseudo_ipc.o \
 		$(WRAPOBJS) $(SHOBJS) $(LDFLAGS) $(CLIENT_LDFLAGS)
 
 # *everything* now relies on stuff that's generated in the
@@ -135,6 +135,8 @@ pseudo_client.o pseudo_server.o pseudo_ipc.o: pseudo_ipc.h
 
 pseudo_client.o: pseudo_client.h
 
+pseudo_client_scanf.o: pseudo_client.h
+
 pseudo_server.o: pseudo_server.h
 
 tables: enums/*.in maketables templatefile.py $(TABLES)
diff --git a/ports/unix/guts/linkat.c b/ports/unix/guts/linkat.c
index 7d8dff4..e1712a9 100644
--- a/ports/unix/guts/linkat.c
+++ b/ports/unix/guts/linkat.c
@@ -55,7 +55,7 @@
 		errno = ENOSYS;
 		return -1;
 #endif
-		tmpfile_fd = atoi(oldpath + 14);
+		tmpfile_fd = pseudo_atoi_wrapper(oldpath + 14);
 		// call actual link
 		rc = real_linkat(AT_FDCWD, oldpath, AT_FDCWD, newpath, AT_SYMLINK_FOLLOW);
 	} else
diff --git a/pseudo.c b/pseudo.c
index e98e5d6..132d24a 100644
--- a/pseudo.c
+++ b/pseudo.c
@@ -212,7 +212,7 @@ main(int argc, char *argv[]) {
 			opt_S = 1;
 			break;
 		case 't': /* timeout */
-			pseudo_server_timeout = strtol(optarg, &s, 10);
+			pseudo_server_timeout = pseudo_strtol_wrapper(optarg, &s, 10);
 			if (*s && !isspace(*s)) {
 				pseudo_diag("Timeout must be an integer value.\n");
 				usage(EXIT_FAILURE);
diff --git a/pseudo.h b/pseudo.h
index 4b5eaab..b6c13f2 100644
--- a/pseudo.h
+++ b/pseudo.h
@@ -85,6 +85,10 @@ extern int pseudo_etc_file(const char *filename, char *realname, int flags, cons
 extern void pseudo_stat32_from64(struct stat *, const struct stat64 *);
 extern void pseudo_stat64_from32(struct stat64 *, const struct stat *);
 
+extern long pseudo_strtol_wrapper(const char *, char **, int);
+extern long long pseudo_strtoll_wrapper(const char *, char **, int);
+extern int pseudo_atoi_wrapper(const char *);
+
 extern char *pseudo_version;
 
 #ifndef PSEUDO_BINDIR
diff --git a/pseudo_client.c b/pseudo_client.c
index a03d6b1..1cc7a92 100644
--- a/pseudo_client.c
+++ b/pseudo_client.c
@@ -614,7 +614,7 @@ pseudo_init_client(void) {
 			 * at all.
 			 */
 			if (*env) {
-				pseudo_nosymlinkexp = strtol(env, &endptr, 10);
+				pseudo_nosymlinkexp = pseudo_strtol_wrapper(env, &endptr, 10);
 				if (*endptr)
 					pseudo_nosymlinkexp = 1;
 			} else {
@@ -624,20 +624,9 @@ pseudo_init_client(void) {
 			pseudo_nosymlinkexp = 0;
 		}
 		free(env);
-		env = pseudo_get_value("PSEUDO_UIDS");
-		if (env)
-			sscanf(env, "%d,%d,%d,%d",
-				&pseudo_ruid, &pseudo_euid,
-				&pseudo_suid, &pseudo_fuid);
-		free(env);
-
-		env = pseudo_get_value("PSEUDO_GIDS");
-		if (env)
-			sscanf(env, "%d,%d,%d,%d",
-				&pseudo_rgid, &pseudo_egid,
-				&pseudo_sgid, &pseudo_fuid);
-		free(env);
 
+		readenv_uids();
+		readenv_gids();
 		env = pseudo_get_value("PSEUDO_CHROOT");
 		if (env) {
 			pseudo_chroot = strdup(env);
@@ -1030,7 +1019,7 @@ client_spawn_server(void) {
 			pseudo_pidfile = pseudo_localstatedir_path(PSEUDO_PIDFILE);
 			fp = fopen(pseudo_pidfile, "r");
 			if (fp) {
-				if (fscanf(fp, "%d", &server_pid) != 1) {
+				if (read_pidfile(fp, &server_pid) != 1) {
 					pseudo_debug(PDBGF_CLIENT, "Opened server PID file, but didn't get a pid.\n");
 				}
 				fclose(fp);
@@ -1295,7 +1284,7 @@ pseudo_client_setup(void) {
 	fp = fopen(pseudo_pidfile, "r");
 	free(pseudo_pidfile);
 	if (fp) {
-		if (fscanf(fp, "%d", &server_pid) != 1) {
+		if (read_pidfile(fp, &server_pid) != 1) {
 			pseudo_debug(PDBGF_CLIENT, "Opened server PID file, but didn't get a pid.\n");
 		}
 		fclose(fp);
diff --git a/pseudo_client.h b/pseudo_client.h
index d7944ce..e963d95 100644
--- a/pseudo_client.h
+++ b/pseudo_client.h
@@ -74,6 +74,10 @@ extern int pseudo_nosymlinkexp;
 
 extern int pseudo_umask;
 
+extern void readenv_uids(void);
+extern void readenv_gids(void);
+extern int read_pidfile(FILE *, int *);
+
 /* Root can read and write files, and enter directories which have no
  * read, write, or execute permissions.  (But can't execute files without
  * execute permissions!)
diff --git a/pseudo_client_scanf.c b/pseudo_client_scanf.c
new file mode 100644
index 0000000..4a55d5d
--- /dev/null
+++ b/pseudo_client_scanf.c
@@ -0,0 +1,39 @@
+#include <stdio.h>
+#include "pseudo.h"
+#include "pseudo_ipc.h"
+#include "pseudo_client.h"
+
+/*
+ * glibc 2.38 would include  __isoc23_strtol and similar symbols if _GNU_SOURCE
+ * is used. We have to set that for other definitions so delcare this wrapper
+ * in a context where we don't have that set.
+ *
+ * We need to wrap strtol, strtoll, atoi, fscanf and sscanf.
+ */
+
+void readenv_uids(void)
+{
+	char *env;
+	env = pseudo_get_value("PSEUDO_UIDS");
+	if (env)
+		sscanf(env, "%d,%d,%d,%d",
+			&pseudo_ruid, &pseudo_euid,
+			&pseudo_suid, &pseudo_fuid);
+	free(env);
+}
+
+void readenv_gids(void)
+{
+	char *env;
+	env = pseudo_get_value("PSEUDO_GIDS");
+	if (env)
+		sscanf(env, "%d,%d,%d,%d",
+			&pseudo_rgid, &pseudo_egid,
+			&pseudo_sgid, &pseudo_fuid);
+	free(env);
+}
+
+int read_pidfile(FILE *fp, int *server_pid)
+{
+	return fscanf(fp, "%d", server_pid);
+}
diff --git a/pseudo_util.c b/pseudo_util.c
index 24115ff..081b8d2 100644
--- a/pseudo_util.c
+++ b/pseudo_util.c
@@ -229,7 +229,7 @@ pseudo_init_util(void) {
 	env = pseudo_get_value("PSEUDO_DEBUG");
 	if (env) {
 		int i;
-		int level = atoi(env);
+		int level = pseudo_atoi_wrapper(env);
 		if (level > 0) {
 			for (i = 0; i < level; ++i) {
 				pseudo_debug_verbose();
diff --git a/pseudolog.c b/pseudolog.c
index ad04753..44f7dbf 100644
--- a/pseudolog.c
+++ b/pseudolog.c
@@ -452,7 +452,7 @@ plog_trait(int opt, char *string) {
 	case PSQF_GID:
 	case PSQF_INODE:
 	case PSQF_UID:
-		new_trait->data.ivalue = strtoll(string, &endptr, 0);
+		new_trait->data.ivalue = pseudo_strtoll_wrapper(string, &endptr, 0);
 		if (*endptr) {
 			pseudo_diag("Unexpected garbage after number (%llu): '%s'\n",
 				new_trait->data.ivalue, endptr);
@@ -462,7 +462,7 @@ plog_trait(int opt, char *string) {
 		break;
 	case PSQF_MODE:
 	case PSQF_PERM:
-		new_trait->data.ivalue = strtoll(string, &endptr, 8);
+		new_trait->data.ivalue = pseudo_strtoll_wrapper(string, &endptr, 8);
 		if (!*endptr) {
 			break;
 		}
diff --git a/strtol.c b/strtol.c
new file mode 100644
index 0000000..258f02f
--- /dev/null
+++ b/strtol.c
@@ -0,0 +1,26 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include "pseudo.h"
+
+/*
+ * glibc 2.38 would include  __isoc23_strtol and similar symbols if _GNU_SOURCE
+ * is used. We have to set that for other definitions so delcare this wrapper
+ * in a context where we don't have that set.
+ *
+ * We need to wrap strtol, strtoll, atoi, fscanf and sscanf.
+ */
+
+int pseudo_atoi_wrapper(const char *nptr)
+{
+	return atoi(nptr);
+}
+
+long pseudo_strtol_wrapper(const char *nptr, char **endptr, int base)
+{
+	return strtol(nptr, endptr, base);
+}
+
+long long pseudo_strtoll_wrapper(const char *nptr, char **endptr, int base)
+{
+	return strtoll(nptr, endptr, base);
+}