add strdup for debugging.
diff --git a/src/lib9/mkfile b/src/lib9/mkfile
index bea1165..7ade5b6 100644
--- a/src/lib9/mkfile
+++ b/src/lib9/mkfile
@@ -137,6 +137,7 @@
seek.$O\
sendfd.$O\
sleep.$O\
+ strdup.$O\
strecpy.$O\
sysfatal.$O\
sysname.$O\
diff --git a/src/lib9/strdup.c b/src/lib9/strdup.c
new file mode 100644
index 0000000..5ca3186
--- /dev/null
+++ b/src/lib9/strdup.c
@@ -0,0 +1,17 @@
+#include <u.h>
+#include <libc.h>
+
+char*
+strdup(char *s)
+{
+ char *t;
+ int l;
+
+ l = strlen(s);
+ t = malloc(l+1);
+ if(t == nil)
+ return nil;
+ memmove(t, s, l+1);
+ return t;
+}
+
