tools: mkenvimage: Fix read() stdin error handling
On success read() returns the number of bytes read or zero for EOF. On
error -1 is returned and errno is set, so the right way to test if read
had failed is to test the return value instead of errno.
Signed-off-by: Alexander Dahl <ada@thorsis.com>
diff --git a/tools/mkenvimage.c b/tools/mkenvimage.c
index 8eee72e..716cb73 100644
--- a/tools/mkenvimage.c
+++ b/tools/mkenvimage.c
@@ -168,7 +168,7 @@
return EXIT_FAILURE;
}
readbytes = read(txt_fd, filebuf + filesize, readlen);
- if (errno) {
+ if (readbytes < 0) {
fprintf(stderr, "Error while reading stdin: %s\n",
strerror(errno));
return EXIT_FAILURE;