diff --git a/fastboot/fastboot.cpp b/fastboot/fastboot.cpp
index 4cd423a..7f4a0dd 100644
--- a/fastboot/fastboot.cpp
+++ b/fastboot/fastboot.cpp
@@ -43,7 +43,9 @@
 #include <sys/types.h>
 #include <unistd.h>
 
+#include <chrono>
 #include <functional>
+#include <thread>
 #include <utility>
 #include <vector>
 
@@ -301,7 +303,7 @@
             announce = false;
             fprintf(stderr, "< waiting for %s >\n", serial ? serial : "any device");
         }
-        usleep(1000);
+        std::this_thread::sleep_for(std::chrono::milliseconds(1));
     }
 }
 
diff --git a/fastboot/usb_linux.cpp b/fastboot/usb_linux.cpp
index 6db1e27..cdab4f1 100644
--- a/fastboot/usb_linux.cpp
+++ b/fastboot/usb_linux.cpp
@@ -43,11 +43,15 @@
 #include <linux/version.h>
 #include <linux/usb/ch9.h>
 
+#include <chrono>
 #include <memory>
+#include <thread>
 
 #include "fastboot.h"
 #include "usb.h"
 
+using namespace std::chrono_literals;
+
 #define MAX_RETRIES 5
 
 /* Timeout in seconds for usb_wait_for_disconnect.
@@ -426,7 +430,7 @@
         return -1;
     }
 
-    while(len > 0) {
+    while (len > 0) {
         int xfer = (len > MAX_USBFS_BULK_SIZE) ? MAX_USBFS_BULK_SIZE : len;
 
         bulk.ep = handle_->ep_in;
@@ -435,18 +439,17 @@
         bulk.timeout = 0;
         retry = 0;
 
-        do{
-           DBG("[ usb read %d fd = %d], fname=%s\n", xfer, handle_->desc, handle_->fname);
-           n = ioctl(handle_->desc, USBDEVFS_BULK, &bulk);
-           DBG("[ usb read %d ] = %d, fname=%s, Retry %d \n", xfer, n, handle_->fname, retry);
+        do {
+            DBG("[ usb read %d fd = %d], fname=%s\n", xfer, handle_->desc, handle_->fname);
+            n = ioctl(handle_->desc, USBDEVFS_BULK, &bulk);
+            DBG("[ usb read %d ] = %d, fname=%s, Retry %d \n", xfer, n, handle_->fname, retry);
 
-           if( n < 0 ) {
-            DBG1("ERROR: n = %d, errno = %d (%s)\n",n, errno, strerror(errno));
-            if ( ++retry > MAX_RETRIES ) return -1;
-            sleep( 1 );
-           }
-        }
-        while( n < 0 );
+            if (n < 0) {
+                DBG1("ERROR: n = %d, errno = %d (%s)\n",n, errno, strerror(errno));
+                if (++retry > MAX_RETRIES) return -1;
+                std::this_thread::sleep_for(1s);
+            }
+        } while (n < 0);
 
         count += n;
         len -= n;
@@ -488,9 +491,8 @@
 {
   double deadline = now() + WAIT_FOR_DISCONNECT_TIMEOUT;
   while (now() < deadline) {
-    if (access(handle_->fname, F_OK))
-      return 0;
-    usleep(50000);
+    if (access(handle_->fname, F_OK)) return 0;
+    std::this_thread::sleep_for(50ms);
   }
   return -1;
 }
diff --git a/fastboot/usb_windows.cpp b/fastboot/usb_windows.cpp
index 1cdeb32..3dab5ac 100644
--- a/fastboot/usb_windows.cpp
+++ b/fastboot/usb_windows.cpp
@@ -362,9 +362,3 @@
     std::unique_ptr<usb_handle> handle = find_usb_device(callback);
     return handle ? new WindowsUsbTransport(std::move(handle)) : nullptr;
 }
-
-// called from fastboot.c
-void sleep(int seconds)
-{
-    Sleep(seconds * 1000);
-}
diff --git a/init/builtins.cpp b/init/builtins.cpp
index 94dc832..ebdc8c9 100644
--- a/init/builtins.cpp
+++ b/init/builtins.cpp
@@ -38,6 +38,8 @@
 #include <linux/loop.h>
 #include <linux/module.h>
 
+#include <thread>
+
 #include <selinux/selinux.h>
 #include <selinux/label.h>
 
@@ -65,7 +67,6 @@
 #include "util.h"
 
 #define chmod DO_NOT_USE_CHMOD_USE_FCHMODAT_SYMLINK_NOFOLLOW
-#define UNMOUNT_CHECK_MS 5000
 #define UNMOUNT_CHECK_TIMES 10
 
 static constexpr std::chrono::nanoseconds kCommandRetryTimeout = 5s;
@@ -192,11 +193,9 @@
             close(fd);
             break;
         } else if (errno == EBUSY) {
-            /* Some processes using |entry->mnt_dir| are still alive. Wait for a
-             * while then retry.
-             */
-            TEMP_FAILURE_RETRY(
-                usleep(UNMOUNT_CHECK_MS * 1000 / UNMOUNT_CHECK_TIMES));
+            // Some processes using |entry->mnt_dir| are still alive. Wait for a
+            // while then retry.
+            std::this_thread::sleep_for(5000ms / UNMOUNT_CHECK_TIMES);
             continue;
         } else {
             /* Cannot open the device. Give up. */
@@ -749,7 +748,7 @@
             }
 
             // Wait a bit before recounting the number or running services.
-            usleep(50000 /*us*/);
+            std::this_thread::sleep_for(50ms);
         }
         LOG(VERBOSE) << "Terminating running services took " << t.duration() << " seconds";
     }
diff --git a/init/devices.cpp b/init/devices.cpp
index d422ba7..5098fb3 100644
--- a/init/devices.cpp
+++ b/init/devices.cpp
@@ -35,6 +35,7 @@
 #include <linux/netlink.h>
 
 #include <memory>
+#include <thread>
 
 #include <selinux/selinux.h>
 #include <selinux/label.h>
@@ -841,7 +842,7 @@
     if (booting) {
         // If we're not fully booted, we may be missing
         // filesystems needed for firmware, wait and retry.
-        usleep(100000);
+        std::this_thread::sleep_for(100ms);
         booting = is_booting();
         goto try_loading_again;
     }
diff --git a/init/util.cpp b/init/util.cpp
index bde4efb..cb5a094 100644
--- a/init/util.cpp
+++ b/init/util.cpp
@@ -34,6 +34,8 @@
 #include <sys/types.h>
 #include <sys/un.h>
 
+#include <thread>
+
 #include <android-base/file.h>
 #include <android-base/logging.h>
 #include <android-base/stringprintf.h>
@@ -326,7 +328,7 @@
         struct stat sb;
         if (stat(filename, &sb) != -1) return 0;
 
-        usleep(10000);
+        std::this_thread::sleep_for(10ms);
     }
     return -1;
 }
diff --git a/libprocessgroup/processgroup.cpp b/libprocessgroup/processgroup.cpp
index 7c15429..eb66727 100644
--- a/libprocessgroup/processgroup.cpp
+++ b/libprocessgroup/processgroup.cpp
@@ -31,12 +31,15 @@
 #include <chrono>
 #include <memory>
 #include <mutex>
+#include <thread>
 
 #include <android-base/logging.h>
 #include <private/android_filesystem_config.h>
 
 #include <processgroup/processgroup.h>
 
+using namespace std::chrono_literals;
+
 // Uncomment line below use memory cgroups for keeping track of (forked) PIDs
 // #define USE_MEMCG 1
 
@@ -288,7 +291,7 @@
     while ((processes = killProcessGroupOnce(uid, initialPid, signal)) > 0) {
         LOG(VERBOSE) << "killed " << processes << " processes for processgroup " << initialPid;
         if (retry > 0) {
-            usleep(5 * 1000); // 5ms
+            std::this_thread::sleep_for(5ms);
             --retry;
         } else {
             LOG(ERROR) << "failed to kill " << processes << " processes for processgroup "