Switch from returning -1 to -errno so that callers can determine types
of failure.

Signed-off-by: Ian Rogers <irogers@google.com>
---
 tools/lib/api/fs/fs.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/tools/lib/api/fs/fs.c b/tools/lib/api/fs/fs.c
index 337fde770e45..edec23406dbc 100644
--- a/tools/lib/api/fs/fs.c
+++ b/tools/lib/api/fs/fs.c
@@ -296,7 +296,7 @@ int filename__read_int(const char *filename, int *value)
 	int fd = open(filename, O_RDONLY), err = -1;
 
 	if (fd < 0)
-		return -1;
+		return -errno;
 
 	if (read(fd, line, sizeof(line)) > 0) {
 		*value = atoi(line);
@@ -314,7 +314,7 @@ static int filename__read_ull_base(const char *filename,
 	int fd = open(filename, O_RDONLY), err = -1;
 
 	if (fd < 0)
-		return -1;
+		return -errno;
 
 	if (read(fd, line, sizeof(line)) > 0) {
 		*value = strtoull(line, NULL, base);
@@ -372,7 +372,7 @@ int filename__write_int(const char *filename, int value)
 	char buf[64];
 
 	if (fd < 0)
-		return err;
+		return -errno;
 
 	sprintf(buf, "%d", value);
 	if (write(fd, buf, sizeof(buf)) == sizeof(buf))
-- 
2.47.0.338.g60cca15819-goog