1 files changed, 16 insertions, 8 deletions

diff --git a/src/pacman/util.c b/src/pacman/util.c
index 2671e54c..3f2ed83b 100644
--- a/src/pacman/util.c
+++ b/src/pacman/util.c
@@ -46,7 +46,7 @@
 #include "conf.h"
 #include "callback.h"
 
-static int cached_columns = 0;
+static int cached_columns = -1;
 
 struct table_cell_t {
 	char *label;
@@ -158,13 +158,17 @@ static int flush_term_input(int fd)
 
 void columns_cache_reset(void)
 {
-	cached_columns = 0;
+	cached_columns = -1;
 }
 
 static int getcols_fd(int fd)
 {
 	int width = -1;
 
+	if(!isatty(fd)) {
+		return 0;
+	}
+
 #if defined(TIOCGSIZE)
 	struct ttysize win;
 	if(ioctl(fd, TIOCGSIZE, &win) == 0) {
@@ -187,22 +191,26 @@ static int getcols_fd(int fd)
 unsigned short getcols(void)
 {
 	const char *e;
-	int c = 0;
+	int c = -1;
 
-	if(cached_columns > 0) {
+	if(cached_columns >= 0) {
 		return cached_columns;
 	}
 
 	e = getenv("COLUMNS");
-	if(e) {
-		c = strtol(e, NULL, 10);
+	if(e && *e) {
+		char *p = NULL;
+		c = strtol(e, &p, 10);
+		if(*p != '\0') {
+			c= -1;
+		}
 	}
 
-	if(c <= 0) {
+	if(c < 0) {
 		c = getcols_fd(STDOUT_FILENO);
 	}
 
-	if(c <= 0) {
+	if(c < 0) {
 		c = 80;
 	}