Subject: [PATCH v3 09/13] print errno when reporting a system call error

From: Junio C Hamano <[email-masked]>
Date: Fri, 26 May 2017 12:35:06 +0900

From: Nguyễn Thái Ngọc Duy <[email-masked]>

Signed-off-by: Nguyễn Thái Ngọc Duy <[email-masked]>
Signed-off-by: Junio C Hamano <[email-masked]>
---
 builtin/log.c     | 3 ++-
 rerere.c          | 4 ++--
 xdiff-interface.c | 4 ++--
 3 files changed, 6 insertions(+), 5 deletions(-)

diff --git a/builtin/log.c b/builtin/log.c
index b3b10cc1ed..26d6a3cf14 100644
--- a/builtin/log.c
+++ b/builtin/log.c
@@ -858,7 +858,8 @@ static int open_next_file(struct commit *commit, const char *subject,
 		printf("%s\n", filename.buf + outdir_offset);
 
 	if ((rev->diffopt.file = fopen(filename.buf, "w")) == NULL)
-		return error(_("Cannot open patch file %s"), filename.buf);
+		return error_errno(_("Cannot open patch file %s"),
+				   filename.buf);
 
 	strbuf_release(&filename);
 	return 0;
diff --git a/rerere.c b/rerere.c
index 971bfedfb2..1351b0c3fb 100644
--- a/rerere.c
+++ b/rerere.c
@@ -484,13 +484,13 @@ static int handle_file(const char *path, unsigned char *sha1, const char *output
 	io.input = fopen(path, "r");
 	io.io.wrerror = 0;
 	if (!io.input)
-		return error("Could not open %s", path);
+		return error_errno("Could not open %s", path);
 
 	if (output) {
 		io.io.output = fopen(output, "w");
 		if (!io.io.output) {
 			fclose(io.input);
-			return error("Could not write %s", output);
+			return error_errno("Could not write %s", output);
 		}
 	}
 
diff --git a/xdiff-interface.c b/xdiff-interface.c
index 060038c2d6..d3f78ca2a7 100644
--- a/xdiff-interface.c
+++ b/xdiff-interface.c
@@ -164,9 +164,9 @@ int read_mmfile(mmfile_t *ptr, const char *filename)
 	size_t sz;
 
 	if (stat(filename, &st))
-		return error("Could not stat %s", filename);
+		return error_errno("Could not stat %s", filename);
 	if ((f = fopen(filename, "rb")) == NULL)
-		return error("Could not open %s", filename);
+		return error_errno("Could not open %s", filename);
 	sz = xsize_t(st.st_size);
 	ptr->ptr = xmalloc(sz ? sz : 1);
 	if (sz && fread(ptr->ptr, sz, 1, f) != 1) {
-- 
2.13.0-491-g71cfeddc25