8158 Want named threads API
9857 proc manpages should have LIBRARY section

@@ -22,11 +22,11 @@
  * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
  * Use is subject to license terms.
  */
 
 /*
- * Copyright (c) 2013, Joyent, Inc. All rights reserved.
+ * Copyright 2018 Joyent, Inc.
  * Copyright (c) 2013 by Delphix. All rights reserved.
  */
 
 #include <sys/types.h>
 #include <sys/uio.h>

@@ -350,10 +350,42 @@
         }
 
         return (-1);
 }
 
+int
+Plwp_getname(struct ps_prochandle *P, lwpid_t lwpid,
+    char *buf, size_t bufsize)
+{
+        char lwpname[THREAD_NAME_MAX];
+        char *from = NULL;
+        lwp_info_t *lwp;
+
+        if (P->state == PS_IDLE) {
+                errno = ENODATA;
+                return (-1);
+        }
+
+        if (P->state != PS_DEAD) {
+                if (getlwpfile(P, lwpid, "lwpname",
+                    lwpname, sizeof (lwpname)) != 0)
+                        return (-1);
+                from = lwpname;
+        } else {
+                if ((lwp = getlwpcore(P, lwpid)) == NULL)
+                        return (-1);
+                from = lwp->lwp_name;
+        }
+
+        if (strlcpy(buf, from, bufsize) >= bufsize) {
+                errno = ENAMETOOLONG;
+                return (-1);
+        }
+
+        return (0);
+}
+
 int
 Plwp_getspymaster(struct ps_prochandle *P, lwpid_t lwpid, psinfo_t *ps)
 {
         lwpstatus_t lps;