Single line sftp from terminal

Several times throughout the day, I may be running a test where I need to look through a log file on a remote server. I've gotten used to using my terminal to sftp into the remote server and pull the desired log file down to /tmp on my local machine.

I was looking through the options today using man sftp in an attempt to figure out a way to run the following commands basically in a single line so that I don't have to type a command, press enter, type a command press enter, etc.

(what I do now)

sftp myuser@myserver
--mypassword at prompt
lcd /tmp
get /dir/dir/dir/dir/file
quit

I found while looking through man sftp a reference to scp which I haven't used before. I feel it may be what I'm looking for, but I didn't see a way to specify where I wanted the securely copied file to go.

Could someone provide me with a way to get /dir/file from a remote server and have it download to /tmp/file_plus-my-description?

I was hoping to be able to run an sftp or scp command similar to a regularUNIX copy like:

scp myuser@myserver /dir/file /tmp/file_plus-my-description

I'm using the built in Terminal in Mac OS X 10.8. Thanks.

Update Sep 2017 - tl;dr

Download a single file from a remote ftp server to your machine:

sftp {user}@{host}:{remoteFileName} {localFileName}

Upload a single file from your machine to a remote ftp server:

sftp {user}@{host}:{remote_dir} <<< $'put {local_file_path}'

---

Original answer:

Ok, so I feel a little dumb. But I figured it out. I almost had it at the top with:

sftp user@host remoteFile localFile

The only documentation shown in the terminal is this:

sftp [user@]host[:file ...]
sftp [user@]host[:dir[/]]

However, I came across this site which shows the following under the synopsis:

sftp [-vC1 ] [-b batchfile ] [-o ssh_option ] [-s subsystem | sftp_server ] [-B buffer_size ] [-F ssh_config ] [-P sftp_server path ] [-R num_requests ] [-S program ] host 
sftp [[user@]host[:file [file]]] 
sftp [[user@]host[:dir[/]]]

So the simple answer is you just do : after your user and host then the remote file and local filename. Incredibly simple!

Single line, sftp copy remote file:

sftp username@hostname:remoteFileName localFileName
sftp kyle@kylesserver:/tmp/myLogFile.log /tmp/fileNameToUseLocally.log

Update Feb 2016

In case anyone is looking for the command to do the reverse of this and push a file from your local computer to a remote server in one single line sftp command, user @Thariama below posted the solution to accomplish that. Hat tip to them for the extra code.

sftp {user}@{host}:{remote_dir} <<< $'put {local_file_path}'

SCP answer

The OP mentioned SCP, so here's that.

As others have pointed out, SFTP is a confusing since the upload syntax is completely different from the download syntax. It gets marginally easier to remember if you use the same form:

echo 'put LOCALPATH REMOTEPATH' | sftp USER@HOST
echo 'get REMOTEPATH LOCALPATH' | sftp USER@HOST

In reality, this is still a mess, and is why people still use "outdated" commands such as SCP:

scp USER@HOST:REMOTEPATH LOCALPATH
scp LOCALPATH USER@HOST:REMOTEPATH

SCP is secure but dated. It has some bugs that will never be fixed, namely crashing if the server's .bash_profile emits a message. However, in terms of usability, the devs were years ahead.

To UPLOAD a single file, you will need to create a bash script. Something like the following should work on OS X if you have sshpass installed.

Usage:

sftpx <password> <user@hostname> <localfile> <remotefile>

Put this script somewhere in your path and call it sftpx:

#!/bin/bash

export RND=`cat /dev/urandom | env LC_CTYPE=C tr -cd 'a-f0-9' | head -c 32`
export TMPDIR=/tmp/$RND
export FILENAME=$(basename "$4")
export DSTDIR=$(dirname "$4")

mkdir $TMPDIR
cp "$3" $TMPDIR/$FILENAME

export SSHPASS=$1
sshpass -e sftp -oBatchMode=no -b - $2 << !
   lcd $TMPDIR
   cd $DSTDIR
   put $FILENAME
   bye
!

rm $TMPDIR/$FILENAME
rmdir $TMPDIR

Or echo 'put {path to file}' | sftp {user}@{host}:{dir}, which would work in both unix and powershell.

sftp supports batch files.

From the man page:

-b batchfile

Batch mode reads a series of commands from an input batchfile instead of stdin.  
Since it lacks user interaction it should be used in conjunction with non-interactive
authentication.  A batchfile of `-' may be used to indicate standard input.  sftp 
will abort if any of the following commands fail: get, put, rename, ln, rm, mkdir, 
chdir, ls, lchdir, chmod, chown, chgrp, lpwd, df, symlink, and lmkdir.  Termination 
on error can be suppressed on a command by command basis by prefixing the command 
with a `-' character (for example, -rm /tmp/blah*).

OpenSSH scp supports SFTP protocol since 8.7, via -s parameter.

Download:

scp -s user@host:/remote/source/path /local/target/path

Upload:

scp -s /local/source/path user@host:/remote/target/path

---

The future version of OpenSSH scp will use SFTP by default.

A minor modification like below worked for me when using it from within perl and system() call:

sftp {user}@{host} <<< $'put {local_file_path} {remote_file_path}'