diff --git a/src/include/options.h b/src/include/options.h
index 33f6e26..012363a 100644
--- a/src/include/options.h
+++ b/src/include/options.h
@@ -34,7 +34,7 @@ struct opts_s {           /* structure describing run-time options */
 	bool numeric;                  /* numeric output only */
 	bool wait;                     /* wait for transfer before display */
 	bool linemode;                 /* count lines instead of bytes */
-	bool null;                     /* lines are null-terminated */
+	bool null_terminated_lines;    /* lines are null-terminated */
 	bool no_display;               /* do nothing other than pipe data */
 	unsigned long long rate_limit; /* rate limit, in bytes per second */
 	unsigned long long buffer_size;/* buffer size, in bytes (0=default) */
diff --git a/src/include/pv-internal.h b/src/include/pv-internal.h
index 4a8d988..82a06a4 100644
--- a/src/include/pv-internal.h
+++ b/src/include/pv-internal.h
@@ -89,7 +89,7 @@ struct pvstate_s {
 	bool wait;                       /* wait for data before display */
 	bool linemode;                   /* count lines instead of bytes */
 	bool bits;			 /* report bits instead of bytes */
-	bool null;                       /* lines are null-terminated */
+	bool null_terminated_lines;      /* lines are null-terminated */
 	bool no_display;                 /* do nothing other than pipe data */
 	unsigned int skip_errors;        /* skip read errors counter */
 	bool stop_at_size;               /* set if we stop at "size" bytes */
diff --git a/src/include/pv.h b/src/include/pv.h
index da28249..177cc76 100644
--- a/src/include/pv.h
+++ b/src/include/pv.h
@@ -107,7 +107,7 @@ extern void pv_state_wait_set(pvstate_t, bool);
 extern void pv_state_delay_start_set(pvstate_t, double);
 extern void pv_state_linemode_set(pvstate_t, bool);
 extern void pv_state_bits_set(pvstate_t, bool);
-extern void pv_state_null_set(pvstate_t, bool);
+extern void pv_state_null_terminated_lines_set(pvstate_t, bool);
 extern void pv_state_no_display_set(pvstate_t, bool);
 extern void pv_state_skip_errors_set(pvstate_t, unsigned int);
 extern void pv_state_stop_at_size_set(pvstate_t, bool);
diff --git a/src/main/main.c b/src/main/main.c
index 26d7959..808315a 100644
--- a/src/main/main.c
+++ b/src/main/main.c
@@ -191,7 +191,7 @@ int main(int argc, char **argv)
 		 */
 		if (0 == opts->size) {
 			pv_state_linemode_set(state, opts->linemode);
-			pv_state_null_set(state, opts->null);
+			pv_state_null_terminated_lines_set(state, opts->null_terminated_lines);
 			opts->size = pv_calc_total_size(state);
 			debug("%s: %llu", "no size given - calculated", opts->size);
 		}
@@ -268,7 +268,7 @@ int main(int argc, char **argv)
 	pv_state_delay_start_set(state, opts->delay_start);
 	pv_state_linemode_set(state, opts->linemode);
 	pv_state_bits_set(state, opts->bits);
-	pv_state_null_set(state, opts->null);
+	pv_state_null_terminated_lines_set(state, opts->null_terminated_lines);
 	pv_state_skip_errors_set(state, opts->skip_errors);
 	pv_state_stop_at_size_set(state, opts->stop_at_size);
 	pv_state_sync_after_write_set(state, opts->sync_after_write);
diff --git a/src/main/options.c b/src/main/options.c
index 73f468d..46c1d9c 100644
--- a/src/main/options.c
+++ b/src/main/options.c
@@ -422,7 +422,7 @@ opts_t opts_parse(unsigned int argc, char **argv)
 			opts->linemode = true;
 			break;
 		case '0':
-			opts->null = true;
+			opts->null_terminated_lines = true;
 			opts->linemode = true;
 			break;
 		case 'i':
@@ -529,7 +529,7 @@ opts_t opts_parse(unsigned int argc, char **argv)
 		return NULL;
 
 	if (0 != opts->watch_pid) {
-		if (opts->linemode || opts->null || opts->stop_at_size
+		if (opts->linemode || opts->null_terminated_lines || opts->stop_at_size
 		    || (opts->skip_errors > 0) || (opts->buffer_size > 0)
 		    || (opts->rate_limit > 0)) {
 			/*@-mustfreefresh@ *//* see above */
diff --git a/src/pv/file.c b/src/pv/file.c
index b78b66f..e4f96a9 100644
--- a/src/pv/file.c
+++ b/src/pv/file.c
@@ -199,7 +199,7 @@ static unsigned long long pv_calc_total_lines(pvstate_t state)
 				break;
 			}
 			for (buf_idx = 0; buf_idx < numread; buf_idx++) {
-				if (state->null) {
+				if (state->null_terminated_lines) {
 					if ('\0' == scanbuf[buf_idx])
 						total++;
 				} else {
diff --git a/src/pv/state.c b/src/pv/state.c
index 658ba73..3a4c6ed 100644
--- a/src/pv/state.c
+++ b/src/pv/state.c
@@ -192,9 +192,9 @@ void pv_state_bits_set(pvstate_t state, bool bits)
 	state->bits = bits;
 };
 
-void pv_state_null_set(pvstate_t state, bool val)
+void pv_state_null_terminated_lines_set(pvstate_t state, bool val)
 {
-	state->null = val;
+	state->null_terminated_lines = val;
 };
 
 void pv_state_no_display_set(pvstate_t state, bool val)
diff --git a/src/pv/transfer.c b/src/pv/transfer.c
index b88c9ea..d1d51f8 100644
--- a/src/pv/transfer.c
+++ b/src/pv/transfer.c
@@ -529,7 +529,7 @@ static int pv__transfer_write(pvstate_t state, int *eof_in, int *eof_out, long *
 			state->transfer_buffer[state->write_position + nwritten] = 0;
 			ptr = (char *) (state->transfer_buffer + state->write_position - 1);
 
-			if (state->null) {
+			if (state->null_terminated_lines) {
 				for (ptr++;
 				     ptr -
 				     (char *) state->transfer_buffer -
@@ -861,7 +861,7 @@ long pv_transfer(pvstate_t state, int fd, int *eof_in, int *eof_out, unsigned lo
 	 * In line mode, only write up to and including the last newline,
 	 * so that we're writing output line-by-line.
 	 */
-	if ((state->to_write > 0) && (state->linemode) && !(state->null)) {
+	if ((state->to_write > 0) && (state->linemode) && !(state->null_terminated_lines)) {
 		/*
 		 * Guillaume Marcais: use strrchr to find last \n
 		 */