diff --git a/src/rinex.c b/src/rinex.c
index 398aa8f0a..bf52067d7 100644
--- a/src/rinex.c
+++ b/src/rinex.c
@@ -157,15 +157,6 @@ typedef struct {                        /* signal index type */
     double shift[MAXOBSTYPE];           /* phase shift (cycle) */
 } sigind_t;
 
-/* set string without tail space ---------------------------------------------*/
-static void setstr(char *dst, const char *src, int n)
-{
-    char *p=dst;
-    const char *q=src;
-    while (*q&&q<src+n) *p++=*q++;
-    *p--='\0';
-    while (p>=dst&&*p==' ') *p--='\0';
-}
 /* adjust time considering week handover -------------------------------------*/
 static gtime_t adjweek(gtime_t t, gtime_t t0)
 {
diff --git a/src/rtkcmn.c b/src/rtkcmn.c
index 5ff96f154..fe6aa5beb 100644
--- a/src/rtkcmn.c
+++ b/src/rtkcmn.c
@@ -1550,6 +1550,15 @@ extern void matprint(const double A[], int n, int m, int p, int q)
 {
     matfprint(A,n,m,p,q,stdout);
 }
+/* set string without tail space ---------------------------------------------*/
+extern void setstr(char *dst, const char *src, int n)
+{
+    char *p=dst;
+    const char *q=src;
+    while (*q&&q<src+n) *p++=*q++;
+    *p--='\0';
+    while (p>=dst&&*p==' ') *p--='\0';
+}
 /* string to number ------------------------------------------------------------
 * convert substring in string to number
 * args   : char   *s        I   string ("... nnn.nnn ...")
diff --git a/src/rtklib.h b/src/rtklib.h
index 4c727a045..46716827d 100644
--- a/src/rtklib.h
+++ b/src/rtklib.h
@@ -1415,6 +1415,7 @@ EXPORT void matfprint(const double *A, int n, int m, int p, int q, FILE *fp);
 EXPORT void add_fatal(fatalfunc_t *func);
 
 /* time and string functions -------------------------------------------------*/
+EXPORT void    setstr(char *dst, const char *src, int n);
 EXPORT double  str2num(const char *s, int i, int n);
 EXPORT int     str2time(const char *s, int i, int n, gtime_t *t);
 EXPORT void    time2str(gtime_t t, char *str, int n);