gdb stdout fu ++

Author: cirosantilli

gdb/run

@@ -8,4 +8,4 @@
 #     run watch.out
 
 f="${1%.*}"
-gdb -batch -x "${f}.gdb" "${f}.out"
+gdb -batch -nh -x "${f}.gdb" "${f}.out"

gdb/stdout.c

@@ -3,11 +3,22 @@
 http://stackoverflow.com/questions/1538463/how-can-i-put-a-breakpoint-on-something-is-printed-to-the-terminal-in-gdb
 */
 
+#define _XOPEN_SOURCE 700
 #include <stdio.h>
 #include <stdlib.h>
+#include <unistd.h>
 
 int main() {
-    puts("a");
-    puts("b");
+	write(STDOUT_FILENO, "asdf1", 5);
+	write(STDOUT_FILENO, "qwer1", 5);
+	write(STDOUT_FILENO, "zxcv1", 5);
+	write(STDOUT_FILENO, "qwer2", 5);
+	printf("as");
+	printf("df");
+	printf("qw");
+	printf("er");
+	printf("zx");
+	printf("cv");
+	fflush(stdout);
     return EXIT_SUCCESS;
 }

gdb/stdout.gdb

@@ -2,12 +2,12 @@ start
 define stdout
     catch syscall write
     commands
-        x/s $rsi
-        backtrace
+        printf "rsi = %s\n", $rsi
+        bt
         continue
     end
-    # Stop if it contains arg0.
-    condition 2 $rdi == 1 && strstr((char *)$rsi, "$arg0") != NULL
+    condition $bpnum $rdi == 1 && strstr((char *)$rsi, "$arg0") != NULL
 end
-stdout b
+stdout qwer
+i b
 continue