diff --color -ru a/scp.c b/scp.c

--- a/scp.c	2022-06-30 09:47:39.529662574 +0200

+++ b/scp.c	2022-06-30 09:51:05.740719310 +0200

@@ -1324,12 +1324,12 @@

 	if (src_is_dir && iamrecursive) {

 		if (upload_dir(conn, src, abs_dst, pflag,

-		    SFTP_PROGRESS_ONLY, 0, 0, 1, 1) != 0) {

+		    SFTP_PROGRESS_ONLY, 0, 0, 1, 1, 1) != 0) {

 			error("failed to upload directory %s to %s",

 				src, abs_dst);

 			errs = 1;

 		}

-	} else if (do_upload(conn, src, abs_dst, pflag, 0, 0) != 0) {

+	} else if (do_upload(conn, src, abs_dst, pflag, 0, 0, 1) != 0) {

 		error("failed to upload file %s to %s", src, abs_dst);

 		errs = 1;

 	}

@@ -1566,11 +1566,11 @@

 		debug("Fetching %s to %s\n", g.gl_pathv[i], abs_dst);

 		if (globpath_is_dir(g.gl_pathv[i]) && iamrecursive) {

 			if (download_dir(conn, g.gl_pathv[i], abs_dst, NULL,

-			    pflag, SFTP_PROGRESS_ONLY, 0, 0, 1) == -1)

+			    pflag, SFTP_PROGRESS_ONLY, 0, 0, 1, 1) == -1)

 				err = -1;

 		} else {

 			if (do_download(conn, g.gl_pathv[i], abs_dst, NULL,

-			    pflag, 0, 0) == -1)

+			    pflag, 0, 0, 1) == -1)

 				err = -1;

 		}

 		free(abs_dst);

diff --color -ru a/sftp.c b/sftp.c

--- a/sftp.c	2022-06-30 09:47:39.530662594 +0200

+++ b/sftp.c	2022-06-30 09:52:05.118887441 +0200

@@ -666,12 +666,12 @@

 		if (globpath_is_dir(g.gl_pathv[i]) && (rflag || global_rflag)) {

 			if (download_dir(conn, g.gl_pathv[i], abs_dst, NULL,

 			    pflag || global_pflag, 1, resume,

-			    fflag || global_fflag, 0) == -1)

+			    fflag || global_fflag, 0, 0) == -1)

 				err = -1;

 		} else {

 			if (do_download(conn, g.gl_pathv[i], abs_dst, NULL,

 			    pflag || global_pflag, resume,

-			    fflag || global_fflag) == -1)

+			    fflag || global_fflag, 0) == -1)

 				err = -1;

 		}

 		free(abs_dst);

@@ -760,12 +760,12 @@

 		if (globpath_is_dir(g.gl_pathv[i]) && (rflag || global_rflag)) {

 			if (upload_dir(conn, g.gl_pathv[i], abs_dst,

 			    pflag || global_pflag, 1, resume,

-			    fflag || global_fflag, 0, 0) == -1)

+			    fflag || global_fflag, 0, 0, 0) == -1)

 				err = -1;

 		} else {

 			if (do_upload(conn, g.gl_pathv[i], abs_dst,

 			    pflag || global_pflag, resume,

-			    fflag || global_fflag) == -1)

+			    fflag || global_fflag, 0) == -1)

 				err = -1;

 		}

 	}

diff --color -ru a/sftp-client.c b/sftp-client.c

--- a/sftp-client.c	2022-06-30 09:47:39.530662594 +0200

+++ b/sftp-client.c	2022-06-30 10:03:36.608473570 +0200

@@ -1454,7 +1454,7 @@

 int

 do_download(struct sftp_conn *conn, const char *remote_path,

     const char *local_path, Attrib *a, int preserve_flag, int resume_flag,

-    int fsync_flag)

+    int fsync_flag, int inplace_flag)

 {

 	struct sshbuf *msg;

 	u_char *handle;

@@ -1661,8 +1661,11 @@

 	/* Sanity check */

 	if (TAILQ_FIRST(&requests) != NULL)

 		fatal("Transfer complete, but requests still in queue");

-	/* Truncate at highest contiguous point to avoid holes on interrupt */

-	if (read_error || write_error || interrupted) {

+	/*

+	 * Truncate at highest contiguous point to avoid holes on interrupt,

+	 * or unconditionally if writing in place.

+	 */

+	if (inplace_flag || read_error || write_error || interrupted) {

 		if (reordered && resume_flag) {

 			error("Unable to resume download of \"%s\": "

 			    "server reordered requests", local_path);

@@ -1724,7 +1727,7 @@

 static int

 download_dir_internal(struct sftp_conn *conn, const char *src, const char *dst,

     int depth, Attrib *dirattrib, int preserve_flag, int print_flag,

-    int resume_flag, int fsync_flag, int follow_link_flag)

+    int resume_flag, int fsync_flag, int follow_link_flag, int inplace_flag)

 {

 	int i, ret = 0;

 	SFTP_DIRENT **dir_entries;

@@ -1781,7 +1784,7 @@

 			if (download_dir_internal(conn, new_src, new_dst,

 			    depth + 1, &(dir_entries[i]->a), preserve_flag,

 			    print_flag, resume_flag,

-			    fsync_flag, follow_link_flag) == -1)

+			    fsync_flag, follow_link_flag, inplace_flag) == -1)

 				ret = -1;

 		} else if (S_ISREG(dir_entries[i]->a.perm) ||

 		    (follow_link_flag && S_ISLNK(dir_entries[i]->a.perm))) {

@@ -1793,7 +1796,8 @@

 			if (do_download(conn, new_src, new_dst,

 			    S_ISLNK(dir_entries[i]->a.perm) ? NULL :

 			    &(dir_entries[i]->a),

-			    preserve_flag, resume_flag, fsync_flag) == -1) {

+			    preserve_flag, resume_flag, fsync_flag,

+			    inplace_flag) == -1) {

 				error("Download of file %s to %s failed",

 				    new_src, new_dst);

 				ret = -1;

@@ -1831,7 +1835,7 @@

 int

 download_dir(struct sftp_conn *conn, const char *src, const char *dst,

     Attrib *dirattrib, int preserve_flag, int print_flag, int resume_flag,

-    int fsync_flag, int follow_link_flag)

+    int fsync_flag, int follow_link_flag, int inplace_flag)

 {

 	char *src_canon;

 	int ret;

@@ -1843,26 +1847,25 @@

 	ret = download_dir_internal(conn, src_canon, dst, 0,

 	    dirattrib, preserve_flag, print_flag, resume_flag, fsync_flag,

-	    follow_link_flag);

+	    follow_link_flag, inplace_flag);

 	free(src_canon);

 	return ret;

 }

 int

 do_upload(struct sftp_conn *conn, const char *local_path,

-    const char *remote_path, int preserve_flag, int resume, int fsync_flag)

+    const char *remote_path, int preserve_flag, int resume,

+    int fsync_flag, int inplace_flag)

 {

 	int r, local_fd;

-	u_int status = SSH2_FX_OK;

-	u_int id;

-	u_char type;

+	u_int openmode, id, status = SSH2_FX_OK, reordered = 0;

 	off_t offset, progress_counter;

-	u_char *handle, *data;

+	u_char type, *handle, *data;

 	struct sshbuf *msg;

 	struct stat sb;

-	Attrib a, *c = NULL;

-	u_int32_t startid;

-	u_int32_t ackid;

+	Attrib a, t, *c = NULL;

+	u_int32_t startid, ackid;

+	u_int64_t highwater = 0;

 	struct request *ack = NULL;

 	struct requests acks;

 	size_t handle_len;

@@ -1913,10 +1916,15 @@

 		}

 	}

+	openmode = SSH2_FXF_WRITE|SSH2_FXF_CREAT;

+	if (resume)

+		openmode |= SSH2_FXF_APPEND;

+	else if (!inplace_flag)

+		openmode |= SSH2_FXF_TRUNC;

+

 	/* Send open request */

-	if (send_open(conn, remote_path, "dest", SSH2_FXF_WRITE|SSH2_FXF_CREAT|

-	    (resume ? SSH2_FXF_APPEND : SSH2_FXF_TRUNC),

-	    &a, &handle, &handle_len) != 0) {

+	if (send_open(conn, remote_path, "dest", openmode, &a,

+	    &handle, &handle_len) != 0) {

 		close(local_fd);

 		return -1;

 	}

@@ -1999,6 +2007,12 @@

 			    ack->id, ack->len, (unsigned long long)ack->offset);

 			++ackid;

 			progress_counter += ack->len;

+			if (!reordered && ack->offset <= highwater)

+				highwater = ack->offset + ack->len;

+			else if (!reordered && ack->offset > highwater) {

+				debug3_f("server reordered ACKs");

+				reordered = 1;

+			}

 			free(ack);

 		}

 		offset += len;

@@ -2017,6 +2031,14 @@

 		status = SSH2_FX_FAILURE;

 	}

+	if (inplace_flag || (resume && (status != SSH2_FX_OK || interrupted))) {

+		debug("truncating at %llu", (unsigned long long)highwater);

+		attrib_clear(&t);

+		t.flags = SSH2_FILEXFER_ATTR_SIZE;

+		t.size = highwater;

+		do_fsetstat(conn, handle, handle_len, &t);

+	}

+

 	if (close(local_fd) == -1) {

 		error("Couldn't close local file \"%s\": %s", local_path,

 		    strerror(errno));

@@ -2041,7 +2063,7 @@

 static int

 upload_dir_internal(struct sftp_conn *conn, const char *src, const char *dst,

     int depth, int preserve_flag, int print_flag, int resume, int fsync_flag,

-    int follow_link_flag)

+    int follow_link_flag, int inplace_flag)

 {

 	int ret = 0;

 	DIR *dirp;

@@ -2119,12 +2141,13 @@

 			if (upload_dir_internal(conn, new_src, new_dst,

 			    depth + 1, preserve_flag, print_flag, resume,

-			    fsync_flag, follow_link_flag) == -1)

+			    fsync_flag, follow_link_flag, inplace_flag) == -1)

 				ret = -1;

 		} else if (S_ISREG(sb.st_mode) ||

 		    (follow_link_flag && S_ISLNK(sb.st_mode))) {

 			if (do_upload(conn, new_src, new_dst,

-			    preserve_flag, resume, fsync_flag) == -1) {

+			    preserve_flag, resume, fsync_flag,

+			    inplace_flag) == -1) {

 				error("Uploading of file %s to %s failed!",

 				    new_src, new_dst);

 				ret = -1;

@@ -2144,7 +2167,7 @@

 int

 upload_dir(struct sftp_conn *conn, const char *src, const char *dst,

     int preserve_flag, int print_flag, int resume, int fsync_flag,

-    int follow_link_flag, int create_dir)

+    int follow_link_flag, int create_dir, int inplace_flag)

 {

 	char *dst_canon;

 	int ret;

@@ -2155,7 +2178,7 @@

 	}

 	ret = upload_dir_internal(conn, src, dst_canon, 0, preserve_flag,

-	    print_flag, resume, fsync_flag, follow_link_flag);

+	    print_flag, resume, fsync_flag, follow_link_flag, inplace_flag);

 	free(dst_canon);

 	return ret;

diff --color -ru a/sftp-client.h b/sftp-client.h

--- a/sftp-client.h	2022-06-30 09:47:39.530662594 +0200

+++ b/sftp-client.h	2022-06-30 10:05:50.835107759 +0200

@@ -138,28 +138,29 @@

  * Download 'remote_path' to 'local_path'. Preserve permissions and times

  * if 'pflag' is set

  */

-int do_download(struct sftp_conn *, const char *, const char *,

-    Attrib *, int, int, int);

+int do_download(struct sftp_conn *, const char *, const char *, Attrib *,

+    int, int, int, int);

 /*

  * Recursively download 'remote_directory' to 'local_directory'. Preserve

  * times if 'pflag' is set

  */

-int download_dir(struct sftp_conn *, const char *, const char *,

-    Attrib *, int, int, int, int, int);

+int download_dir(struct sftp_conn *, const char *, const char *, Attrib *,

+    int, int, int, int, int, int);

 /*

  * Upload 'local_path' to 'remote_path'. Preserve permissions and times

  * if 'pflag' is set

  */

-int do_upload(struct sftp_conn *, const char *, const char *, int, int, int);

+int do_upload(struct sftp_conn *, const char *, const char *,

+    int, int, int, int);

 /*

  * Recursively upload 'local_directory' to 'remote_directory'. Preserve

  * times if 'pflag' is set

  */

-int upload_dir(struct sftp_conn *, const char *, const char *, int, int, int,

-    int, int, int);

+int upload_dir(struct sftp_conn *, const char *, const char *,

+    int, int, int, int, int, int, int);

 /*

  * Download a 'from_path' from the 'from' connection and upload it to