diff --git a/include/patty/ax25/sock.h b/include/patty/ax25/sock.h
index 4185b12..3714e7c 100644
--- a/include/patty/ax25/sock.h
+++ b/include/patty/ax25/sock.h
@@ -116,11 +116,11 @@ ssize_t patty_ax25_sock_send_rej(patty_ax25_sock *sock,
 ssize_t patty_ax25_sock_send_srej(patty_ax25_sock *sock,
                                   enum patty_ax25_frame_cr cr);
 
-ssize_t patty_ax25_sock_send_sabm(patty_ax25_sock *sock, int flag);
+ssize_t patty_ax25_sock_send_sabm(patty_ax25_sock *sock, int pf);
 
-ssize_t patty_ax25_sock_send_sabme(patty_ax25_sock *sock, int flag);
+ssize_t patty_ax25_sock_send_sabme(patty_ax25_sock *sock, int pf);
 
-ssize_t patty_ax25_sock_send_disc(patty_ax25_sock *sock, int flag);
+ssize_t patty_ax25_sock_send_disc(patty_ax25_sock *sock, int pf);
 
 ssize_t patty_ax25_sock_write(patty_ax25_sock *sock,
                               void *buf,
diff --git a/src/sock.c b/src/sock.c
index baf38e3..9f52eee 100644
--- a/src/sock.c
+++ b/src/sock.c
@@ -314,9 +314,9 @@ static uint16_t control_s(patty_ax25_sock *sock,
 }
 
 static uint16_t control_u(enum patty_ax25_frame_type type,
-                          int flag) {
+                          int pf) {
     return (type & PATTY_AX25_FRAME_U_MASK)
-         | (flag << 4);
+         | (pf << 4);
 }
 
 ssize_t patty_ax25_sock_send_rr(patty_ax25_sock *sock,
@@ -355,26 +355,26 @@ ssize_t patty_ax25_sock_send_srej(patty_ax25_sock *sock,
                                 0);
 }
 
-ssize_t patty_ax25_sock_send_sabm(patty_ax25_sock *sock, int flag) {
+ssize_t patty_ax25_sock_send_sabm(patty_ax25_sock *sock, int pf) {
     return patty_ax25_sock_send(sock,
                                 PATTY_AX25_FRAME_COMMAND,
-                                control_u(PATTY_AX25_FRAME_SABM, flag),
+                                control_u(PATTY_AX25_FRAME_SABM, pf),
                                 NULL,
                                 0);
 }
 
-ssize_t patty_ax25_sock_send_sabme(patty_ax25_sock *sock, int flag) {
+ssize_t patty_ax25_sock_send_sabme(patty_ax25_sock *sock, int pf) {
     return patty_ax25_sock_send(sock,
                                 PATTY_AX25_FRAME_COMMAND,
-                                control_u(PATTY_AX25_FRAME_SABME, flag),
+                                control_u(PATTY_AX25_FRAME_SABME, pf),
                                 NULL,
                                 0);
 }
 
-ssize_t patty_ax25_sock_send_disc(patty_ax25_sock *sock, int flag) {
+ssize_t patty_ax25_sock_send_disc(patty_ax25_sock *sock, int pf) {
     return patty_ax25_sock_send(sock,
                                 PATTY_AX25_FRAME_COMMAND,
-                                control_u(PATTY_AX25_FRAME_DISC, flag),
+                                control_u(PATTY_AX25_FRAME_DISC, pf),
                                 NULL,
                                 0);
 }