SSH ChannelReceiveUntilMatchN (Match Any of Several Prompts)

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Demonstrates ChannelReceiveUntilMatchN, which receives until any one of several patterns is matched. This is useful when driving an interactive session where the shell prompt differs from device to device.

Note: This example deliberately requests a PTY. Matching a shell prompt only works in an interactive session — without a PTY the shell runs non-interactively and never prints a prompt at all. For scripted use, omit the PTY and match on a marker your own command echoes.

load ./chilkat.dll

set success 0

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

#  Demonstrates ChannelReceiveUntilMatchN, which receives until ANY one of several patterns is
#  matched.  This is useful when driving an interactive session where the shell prompt varies
#  from device to device.
#  
#  Note: This example deliberately DOES request a PTY.  Matching a shell prompt only works in an
#  interactive session -- without a PTY the shell runs non-interactively and never prints a
#  prompt at all.  For scripted use where no prompt is needed, omit the PTY and match on a
#  marker your own command echoes instead.

set ssh [new_CkSsh]

#  The remote shell prompt may be any of these, depending on the device.
set saPrompts [new_CkStringArray]

CkStringArray_Append $saPrompts "~$"
CkStringArray_Append $saPrompts "mars#"
CkStringArray_Append $saPrompts "jupiter%"
CkStringArray_Append $saPrompts "chilkat$"
CkStringArray_Append $saPrompts "admin>"

set hostname "ssh.example.com"
set port 22
set success [CkSsh_Connect $ssh $hostname $port]
if {$success == 0} then {
    puts [CkSsh_lastErrorText $ssh]
    delete_CkSsh $ssh
    delete_CkStringArray $saPrompts
    exit
}

#  Normally you would not hard-code the password in source.  You should instead obtain it
#  from an interactive prompt, environment variable, or a secrets vault.
set password "mySshPassword"

set success [CkSsh_AuthenticatePw $ssh "mySshLogin" $password]
if {$success == 0} then {
    puts [CkSsh_lastErrorText $ssh]
    delete_CkSsh $ssh
    delete_CkStringArray $saPrompts
    exit
}

set channelNum [CkSsh_OpenSessionChannel $ssh]
if {$channelNum < 0} then {
    puts [CkSsh_lastErrorText $ssh]
    delete_CkSsh $ssh
    delete_CkStringArray $saPrompts
    exit
}

#  Request a pseudo-terminal so the shell runs interactively and prints prompts.  A "dumb"
#  terminal is used so that ANSI escape sequences are not mixed into the output.
set termType "dumb"
set widthInChars 120
set heightInChars 40
set pixWidth 0
set pixHeight 0
set success [CkSsh_SendReqPty $ssh $channelNum $termType $widthInChars $heightInChars $pixWidth $pixHeight]
if {$success == 0} then {
    puts [CkSsh_lastErrorText $ssh]
    delete_CkSsh $ssh
    delete_CkStringArray $saPrompts
    exit
}

set success [CkSsh_SendReqShell $ssh $channelNum]
if {$success == 0} then {
    puts [CkSsh_lastErrorText $ssh]
    delete_CkSsh $ssh
    delete_CkStringArray $saPrompts
    exit
}

#  IMPORTANT: Set a read timeout before receiving until a match.  ReadTimeoutMs defaults to 0,
#  which means no limit -- without it, this call waits forever if the received data never
#  contains a match.
CkSsh_put_ReadTimeoutMs $ssh 15000

set caseSensitive 1

#  Read the initial login text up to the first prompt.
set success [CkSsh_ChannelReceiveUntilMatchN $ssh $channelNum $saPrompts "utf-8" $caseSensitive]
if {$success == 0} then {
    puts [CkSsh_lastErrorText $ssh]
    delete_CkSsh $ssh
    delete_CkStringArray $saPrompts
    exit
}

set cmdOutput [CkSsh_getReceivedText $ssh $channelNum "utf-8"]
if {[CkSsh_get_LastMethodSuccess $ssh] == 0} then {
    puts [CkSsh_lastErrorText $ssh]
    delete_CkSsh $ssh
    delete_CkStringArray $saPrompts
    exit
}

puts "$cmdOutput"

#  ---- 1st command ----
set success [CkSsh_ChannelSendString $ssh $channelNum "cd /tmp\n" "utf-8"]
if {$success == 0} then {
    puts [CkSsh_lastErrorText $ssh]
    delete_CkSsh $ssh
    delete_CkStringArray $saPrompts
    exit
}

set success [CkSsh_ChannelReceiveUntilMatchN $ssh $channelNum $saPrompts "utf-8" $caseSensitive]
if {$success == 0} then {
    puts [CkSsh_lastErrorText $ssh]
    delete_CkSsh $ssh
    delete_CkStringArray $saPrompts
    exit
}

#  Retrieving the text also clears the receive buffer, which matters: if a prompt were left
#  buffered, the next receive would match it immediately and return the wrong output.
set cmdOutput [CkSsh_getReceivedText $ssh $channelNum "utf-8"]
if {[CkSsh_get_LastMethodSuccess $ssh] == 0} then {
    puts [CkSsh_lastErrorText $ssh]
    delete_CkSsh $ssh
    delete_CkStringArray $saPrompts
    exit
}

puts "$cmdOutput"

#  ---- 2nd command ----
set success [CkSsh_ChannelSendString $ssh $channelNum "ls\n" "utf-8"]
if {$success == 0} then {
    puts [CkSsh_lastErrorText $ssh]
    delete_CkSsh $ssh
    delete_CkStringArray $saPrompts
    exit
}

set success [CkSsh_ChannelReceiveUntilMatchN $ssh $channelNum $saPrompts "utf-8" $caseSensitive]
if {$success == 0} then {
    puts [CkSsh_lastErrorText $ssh]
    delete_CkSsh $ssh
    delete_CkStringArray $saPrompts
    exit
}

set cmdOutput [CkSsh_getReceivedText $ssh $channelNum "utf-8"]
if {[CkSsh_get_LastMethodSuccess $ssh] == 0} then {
    puts [CkSsh_lastErrorText $ssh]
    delete_CkSsh $ssh
    delete_CkStringArray $saPrompts
    exit
}

puts "$cmdOutput"

#  Finish the session.
set success [CkSsh_ChannelSendEof $ssh $channelNum]
if {$success == 0} then {
    puts [CkSsh_lastErrorText $ssh]
    delete_CkSsh $ssh
    delete_CkStringArray $saPrompts
    exit
}

set success [CkSsh_ChannelReceiveToClose $ssh $channelNum]
if {$success == 0} then {
    puts [CkSsh_lastErrorText $ssh]
    delete_CkSsh $ssh
    delete_CkStringArray $saPrompts
    exit
}

set cmdOutput [CkSsh_getReceivedText $ssh $channelNum "utf-8"]
if {[CkSsh_get_LastMethodSuccess $ssh] == 0} then {
    puts [CkSsh_lastErrorText $ssh]
    delete_CkSsh $ssh
    delete_CkStringArray $saPrompts
    exit
}

puts "$cmdOutput"

CkSsh_Disconnect $ssh

delete_CkSsh $ssh
delete_CkStringArray $saPrompts