From 5187ccffa29000918ed0e0ab38d6569e01d8b6af Mon Sep 17 00:00:00 2001
From: Emil Lerch <emil@lerch.org>
Date: Thu, 30 Mar 2023 12:05:24 -0700
Subject: [PATCH] add return code handling

---
 lib/i2cdriver/i2cdriver.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/lib/i2cdriver/i2cdriver.c b/lib/i2cdriver/i2cdriver.c
index a3a5ac2..b8ad652 100644
--- a/lib/i2cdriver/i2cdriver.c
+++ b/lib/i2cdriver/i2cdriver.c
@@ -177,7 +177,13 @@ int readFromSerialPort(int fd, uint8_t *b, size_t s)
 
 void writeToSerialPort(int fd, const uint8_t *b, size_t s)
 {
-  write(fd, b, s);
+  if (write(fd, b, s) == -1){
+    printf("WRITE FAILED %u: ", (int)s);
+    int i;
+    for (i = 0; i < s; i++)
+      printf("%02x ", 0xff & b[i]);
+    printf("\n");
+  }
 #ifdef VERBOSE
   printf("WRITE %u: ", (int)s);
   int i;
@@ -526,7 +532,7 @@ int i2c_commands(I2CDriver *sd, int argc, char *argv[])
 
         i2c_monitor(sd, 1);
         printf("[Hit return to exit monitor mode]\n");
-        fgets(line, sizeof(line) - 1, stdin);
+        if (!fgets(line, sizeof(line) - 1, stdin)) return 1;
         i2c_monitor(sd, 0);
       }
       break;