Tcl

SSH Parallel Remote Commands on Single Server

See more SSH Examples

Shows how to execute multiple commands in parallel on a single SSH server and retrieve the command output for each. Tcl

load ./chilkat.dll

set success 0

# This example requires the Chilkat API to have been previously unlocked.
# See Global Unlock Sample for sample code.

set ssh [new_CkSsh]

set port 22
set success [CkSsh_Connect $ssh "the-ssh-server.com" $port]
if {$success != 1} then {
    puts [CkSsh_lastErrorText $ssh]
    delete_CkSsh $ssh
    exit
}

# Authenticate using login/password:
set success [CkSsh_AuthenticatePw $ssh "theSshLogin" "theSshPassword"]
if {$success != 1} then {
    puts [CkSsh_lastErrorText $ssh]
    delete_CkSsh $ssh
    exit
}

# Start several commands on the server.
set channel1 [CkSsh_QuickCmdSend $ssh "df"]
if {$channel1 < 0} then {
    puts [CkSsh_lastErrorText $ssh]
    delete_CkSsh $ssh
    exit
}

set channel2 [CkSsh_QuickCmdSend $ssh "date"]
if {$channel2 < 0} then {
    puts [CkSsh_lastErrorText $ssh]
    delete_CkSsh $ssh
    exit
}

set channel3 [CkSsh_QuickCmdSend $ssh "echo hello world"]
if {$channel3 < 0} then {
    puts [CkSsh_lastErrorText $ssh]
    delete_CkSsh $ssh
    exit
}

# Now collect the results of each command.
set pollTimeoutMs 50
set numFinished 0
while {$numFinished < 3} {
    # Check to see if anything has finished.
    # QuickCmdCheck returns -1 if there are no errors and nothing else finished
    # QuickCmdCheck returns -2 if there was an error (such as a lost connection)
    # QuickCmdCheck returns a channel number if a channel finished.
    set channel [CkSsh_QuickCmdCheck $ssh $pollTimeoutMs]
    if {$channel == -2} then {
        puts [CkSsh_lastErrorText $ssh]
        delete_CkSsh $ssh
        exit
    }

    if {$channel >= 0} then {
        puts "---- channel $channel finished ----"
        puts [CkSsh_getReceivedText $ssh $channel ansi]
        set numFinished [expr $numFinished + 1]
    }

}

# --------------
# Sample output:

# 	---- channel 105 finished ----
# 	hello world
# 
# 	---- channel 104 finished ----
# 	Thu Dec 22 17:43:58 CST 2016
# 
# 	---- channel 103 finished ----
# 	Filesystem    512-blocks      Used  Available Capacity  iused     ifree %iused  Mounted on
# 	/dev/disk2    2176716032 265739728 1910464304    13% 33281464 238808038   12%   /
# 	devfs                382       382          0   100%      662         0  100%   /dev
# 	map -hosts             0         0          0   100%        0         0  100%   /net
# 	map auto_home          0         0          0   100%        0         0  100%   /home
# 	/dev/disk3s2      374668    374668          0   100%    93665         0  100%   /Volumes/Google Chrome

delete_CkSsh $ssh