SFTP creating new directory

Question

I am doing SFTP to transfer files . But during the process , if the path doesn't exists , the sftp is creating a directory bydefault ? Can anyone please explain this to me

Answer 1

With the OpenSSH sftp client, if the local path of the get command contains a directory that does not exist, you will get an error.

This is the code (see the do_download() function in sftp-client.c):

local_fd = open(local_path,
    O_WRONLY | O_CREAT | (resume_flag ? 0 : O_TRUNC), mode | S_IWUSR);
if (local_fd == -1) {
    error("Couldn't open local file \"%s\" for writing: %s",
        local_path, strerror(errno));
    goto fail;
}

No attempt is made to create the directory if it doesn't exist.

Testing this:

sftp> lls hello
ls: hello: No such file or directory
Shell exited with status 1
sftp> get Documents/answers.txt hello/world
Fetching /home/kk/Documents/answers.txt to hello/world
Couldn't open local file "hello/world" for writing: No such file or directory
sftp> lls hello
ls: hello: No such file or directory
Shell exited with status 1
sftp>

If sftp is started with -r or if the get command is used with the same flag, then the destination directory will be created. This is from download_dir_internal() in sftp-client.c which is where we end up from process_get() in sftp.c if the -r flag is used:

if (mkdir(dst, mode) == -1 && errno != EEXIST) {
    error("mkdir %s: %s", dst, strerror(errno));
    return -1;
}

This seems logical to me. If you want to recursively download files, you shouldn't need to manually create the directory structure prior to getting the files.