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NAME
sshexec - run a command through ssh(1) with normal command syntax
SYNOPSIS
sshexec [{ [ssh=ssh-command] [dir=directory] [cd=(strict|lax)]
[[fd]{>,>>,>|,<,<>}[&]=file] [asis=asis-marker
[nasis=asis-count]] }] [ssh-option] ... destination
command [argument] ...
DESCRIPTION
The sshexec utility is a wrapper for SSH that makes it easy to
run commands directly in the SSH command.
sshexec passes any argument after } to ssh-command (ssh if not
specified), but it rewrites command and the arguments to one
argument that can be passed into ssh(1) to describe each argument
as separate arguments. It may also rewrite destination to remove
information that's not supported by ssh(1) and inserts extra
arguments after it (it may also add a -- argument immediately
before destination) to cause the remote shell it change working
directory to directory, if specified, and execute the provided
command and arguments as a regular command rather than as shell
code joined by together by spaces.
OPTIONS
sshexec options may be placed at the very beginning enclosed
with the arguments { and }. sshexec options, if any, shall be
placed in the same { }-group. Any other option will be passed
as is to the ssh(1) utility or ssh-command. The sshexec utility
has a build it list of options recognised by the ssh(1) utility
and will not allow anything matching this list. The sshexec
utility does not allow mixing options and operands: no option
may be placed after destination, such options will be treated
as the command or an argument.
The following sshexec options are supported:
ssh=ssh-command
Instead of looking for ssh in PATH, the sshexec utility
shall use ssh-command, which it will look for in PATH
if it is only a file name (does not contain a slash (/)).
dir=directory
In the remote, change working directory to directory
before executing command.
cd=strict
Fail without executing the command if it's not possible
to set directory as the remote working directory.
cd=lax
Continue (but warn) executing the command even if it's
not possible to set directory as the remote working
directory.
[fd]>=file
After changing working directory (assuming one is
specified), create or truncate the specified file and
open it for writing, using file descriptor number fd.
(Default fd is 1 (standard output).)
[fd]>>=file
After changing working directory (assuming one is
specified), create the specified file if it does not
exist and open it for writing in append-mode, using
file descriptor number fd. (Default fd is 1
(standard output).)
[fd]>|=file
After changing working directory (assuming one is
specified), create the specified file, but fail if it
already exists, and open it for writing, using file
descriptor number fd. (Default fd is 1 (standard
output).)
[fd]<=file
After changing working directory (assuming one is
specified), open the specified file, for reading, using
file descriptor number fd. (Default fd is 0 (standard
input).)
[fd]<>=file
After changing working directory (assuming one is
specified), open the specified file, for reading and
writing, creating it if it does not already exist,
using file descriptor number fd. (Default fd is 0
(standard input).)
[fd]{>,>>,>|}&=file
Duplicate the file descriptor fd giving the new file
descriptor the number file. (Default fd is 1 (standard
output).)
[fd]{>,>>,>|}&=-
Close the file descriptor fd. (Default fd is 1
(standard output).)
[fd]{<,<>}&=file
Duplicate the file descriptor fd giving the new file
descriptor the number file. (Default fd is 0 (standard
input).)
[fd]{<,<>}&=-
Close the file descriptor fd. (Default fd is 0
(standard input).)
asis=asis-marker
Any argument equal to asis-marker will be skipped over
and instead the next argument (regardless of whether
it to is equal to asis-marker) will be interpreted as
raw shell code string that shall be inserted without
escaping.
masis=asis-count
If specified, asis-marker shall only have it's specified
affect up to asis-count times.
OPERANDS
The following operands are supported:
destination
The destination to connect and log into. It shall be
eitherin the form [user@]hostname[:directory] or in the
form ssh[exec]://[user@]hostname[:port][/directory].
user shall be the name of the remote user. If not
specified, the name of the local user running the
utility will be used.
hostname shall be the address to the remote machine.
port shall be the port or service name for the port
to connect to on the remote machine.
directory shall be directory to change the remote
working directory. This is an alternative to (with the
exact same behaviour) to the dir option and cannot be
combined with it.
command [argument] ...
Whereas the ssh(1) utility would simply join the command
and argument arguments with a space between each of
them as pass it to the remote shell for execution, the
sshexec utility forces the remote shell to treat each
of the as separate arguments and cause the shell to
executing them as a non-builtin command.
command must not contain an equals sign (=) or be just
a dash ("-").
ENVIRONMENT VARIABLES
The following environment variables affects the execution of
sshexec:
PATH
Default. See to the Base Definitions volume of POSIX.1-2017,
Section 8.3, Other Environment Variables. This environment
variable affects where the sshexec utility can find the
ssh(1) utility or ssh-command.
SSHEXEC_SSH
If set and non-empty, it overrides the default value of
ssh-command from ssh to the value of the variable.
SSHEXEC_OPTS_NO_ARG
List of options that sshexec shall interpret as ssh(1)
options that do not have any argument. (Default is
46AaCfGgKkMNnqsTtVvXxYy, meaning the options -4, -6, -A,
-a, -C, -f, -G, -g, -K, -k, -M, -N, -n, -q, -s, -T, -t,
-V, -v, -X, -x, -Y, and -y.)
SSHEXEC_OPTS_ARG
List of options that sshexec shall interpret as ssh(1)
options that have an argument. (Default is
BbcDEeFIiJLlmOoPpQRSWw, meaning the options -B, -b, -c,
-D, -E, -e, -F, -I, -i, -J, -L, -l, -m, -O, -o, -P, -p,
-Q, -R, -S, -W, and -w.)
SSHEXEC_OPTS_OPT_ATTACHED_ARG
List of options that sshexec shall interpret as ssh(1)
options that have an argument only if there are
additional characters after the option character in the
same command line argument. (Default is the empty
string, meaning no options.)
SSHEXEC_OPTS_OPT_ARG
List of options that sshexec shall interpret as ssh(1)
options that have an argument if there are additional
characters after the option character in the same
command line argument or if argument is followed
directly by another argument which does not start with
a dash (-). (Default is the empty string, meaning no
options.)
SSHEXEC_LONG_OPTS_NO_ARG
Space-separated list of long options that sshexec shall
interpret as ssh(1) options that do not have any
argument unless it is followed directly by an equals
sign (=) in the same command line argument. Options
that do not start with two dashes (--) are silently
ignored. (Default is the empty string, meaning no
options.)
SSHEXEC_LONG_OPTS_ARG
Space-separated list of long options that sshexec shall
interpret as ssh(1) options that have an argument that
must either be specified in the next command line
argument or after an equals sign (=) the shall directly
follow the option string in the same command line
argument. Options that do not start with two dashes
(--) are silently ignored. (Default is the empty string,
meaning no options.)
SSHEXEC_LONG_OPTS_OPT_ARG
Space-separated list of long options that sshexec shall
interpret as ssh(1) options that have an argument if
it is the option string is is directly followed by
equals sign (=) in the same command line argument or if
argument is followed directly by another argument which
does not start with a dash (-). Options that do not
start with two dashes (--) are silently ignored.
(Default is the empty string, meaning no options.)
Other environment variables may affect the execution of the
ssh(1) utility.
BUGS
The remote shell must be sufficiently similar to sh(1posix).
Namely, it must support the cd builtin command and the commands
exec and printf is expected by POSIX. Additionally, it must
support "$( )", ' ', and &&, and argument separation with the
SP character. The remote shell must also not treat any
alphanumeric character, underscore (_) or slash (/) as special
characters.
SEE ALSO
ssh(1), sshcd(1)
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