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diff --git a/src/lib/user/printf.c b/src/lib/user/printf.c
index d0485f11fd1dfb251c80878925419435a8da80c0..6466e54aaaea8e5f76f46714abf81d3ac5d08c35 100644 (file)
--- a/src/lib/user/printf.c
+++ b/src/lib/user/printf.c
@@ -12,6 +12,9 @@ struct vprintf_aux
     int char_cnt;       /* Total characters written so far. */
   };
 
+/* The standard vprintf() function,
+   which is like printf() but uses a va_list.
+   Writes its output to the STDOUT_FILENO handle. */
 int
 vprintf (const char *format, va_list args) 
 {

diff --git a/src/threads/interrupt.h b/src/threads/interrupt.h
index 5060b9d90bf7d2764b2e1d4e00e785212bca3f7e..adb7fa99b4a424e116914551c4edb0f3d2d30d20 100644 (file)
--- a/src/threads/interrupt.h
+++ b/src/threads/interrupt.h
@@ -36,7 +36,7 @@ struct intr_frame
     uint32_t vec_no;            /* Interrupt vector number. */
 
     /* Sometimes pushed by the CPU,
-       otherwise by intrXX_stub for consistency. */
+       otherwise for consistency pushed as 0 by intrXX_stub. */
     uint32_t error_code;        /* Error code. */
 
     /* Pushed by the CPU.