diff --git a/include/grp.h b/include/grp.h
index 8e2e1f20302cb90b3caaa791e0c8c43a1ade379c..b331d3264c0f1eb4a9844d8a54e4143e514d9609 100644
--- a/include/grp.h
+++ b/include/grp.h
@@ -36,6 +36,7 @@ void           setgrent(void);
 
 #ifdef _GNU_SOURCE
 struct group  *fgetgrent(FILE *stream);
+int putgrent(const struct group *, FILE *);
 #endif
 
 #if defined(_GNU_SOURCE) || defined(_BSD_SOURCE)
diff --git a/include/pwd.h b/include/pwd.h
index 91fe426fe3205227d7576cb3a06b4bd6c4da008c..55d9d42d379e9146d12c8e8a2fcd6f2b15af9288 100644
--- a/include/pwd.h
+++ b/include/pwd.h
@@ -39,6 +39,7 @@ int getpwnam_r (const char *, struct passwd *, char *, size_t, struct passwd **)
 
 #ifdef _GNU_SOURCE
 struct passwd *fgetpwent(FILE *);
+int putpwent(const struct passwd *, FILE *);
 #endif
 
 #ifdef __cplusplus
diff --git a/src/passwd/fgetspent.c b/src/passwd/fgetspent.c
new file mode 100644
index 0000000000000000000000000000000000000000..a9a3c970ee0f1af28225d2c92b0908a1abd27855
--- /dev/null
+++ b/src/passwd/fgetspent.c
@@ -0,0 +1,11 @@
+#include "pwf.h"
+
+struct spwd *fgetspent(FILE *f)
+{
+	return 0;
+}
+
+int putspent(const struct spwd *sp, FILE *f)
+{
+	return -1;
+}
diff --git a/src/passwd/putgrent.c b/src/passwd/putgrent.c
new file mode 100644
index 0000000000000000000000000000000000000000..d7847b15dbb112339b0ff2bead939fb9b612ddcc
--- /dev/null
+++ b/src/passwd/putgrent.c
@@ -0,0 +1,14 @@
+#include <grp.h>
+#include <stdio.h>
+
+int putgrent(const struct group *gr, FILE *f)
+{
+	int r;
+	size_t i;
+	flockfile(f);
+	r = fprintf(f, "%s:%s:%d:", gr->gr_name, gr->gr_passwd, gr->gr_gid);
+	if (gr->gr_mem) for (i=0; gr->gr_mem[i]; i++)
+		if (fprintf(f, "%s%s", i?",":"", gr->gr_mem[i])<0) r = -1;
+	funlockfile(f);
+	return r<0 ? -1 : 0;
+}
diff --git a/src/passwd/putpwent.c b/src/passwd/putpwent.c
new file mode 100644
index 0000000000000000000000000000000000000000..80fbf3843d5e5909f1b6d74644cd1e11ed050b2e
--- /dev/null
+++ b/src/passwd/putpwent.c
@@ -0,0 +1,9 @@
+#include <pwd.h>
+#include <stdio.h>
+
+int putpwent(const struct passwd *pw, FILE *f)
+{
+	return fprintf(f, "%s:%s:%d:%d:%s:%s:%s\n",
+		pw->pw_name, pw->pw_passwd, pw->pw_uid, pw->pw_gid,
+		pw->pw_gecos, pw->pw_dir, pw->pw_shell)<0 ? -1 : 0;
+}