cygwin - Expect while loop dies after 29th iteration -

i'm using expect script within cygwin. reads 2 input files: 1 list of network devices full hostname, , other list of commands run on devices while logging output. works until completing 29th device. when spawn command executes on 30th device, output:

send: spawn id exp65 not open     while executing "send -s "myuserid\r""     ("while" body line 30)     invoked within "while {[gets $switches host] >= 0} {         set hostname [string trimright $host]   ;# rid of trailing whitespace         if {[string length $hostname] == 0} {..."     (file "./getna-lab.exp" line 37) 

to rule out issue cygwin, wanted test mac used expect, can't anymore (devices secured , available via windows virtual desktops, hence cygwin.) @ first thought because "exit" telnet session wasn't working , remaining open, that's not it; tried adding "exit" command list file executes.

the script , other file contents listed below. assistance.

#!/usr/bin/expect  set timeout 600  log_user 0 match_max 100000 set expect_out(buffer) {}  set switchlist [lindex $argv 0] set commandlist [lindex $argv 1]  # # open switch list file # if [catch {open "$switchlist" "r"} switches] {     puts stderr "$cr$switches$ce\n"     exit 1 }  # # verify command list file opens ok before logon, etc. # if [catch {open "$commandlist" "r"} commands] {     puts stderr "$cr$commands$ce\n"     exit 1 } close $commands  # # enable trace logging # trace variable expect_out(buffer) w log_by_tracing  # # loop each device in switch list, looping each command in command list # while {[gets $switches host] >= 0} {     set hostname [string trimright $host]   ;# rid of trailing whitespace     if {[string length $hostname] == 0} {   ;# leave loop if blank line detected         break         }     regexp {^([^\..]+)(\..*$)} $hostname domain hostshort ;# peel off domain name     send_user "\n$hostname:\nworking...\n"     if [catch {open "$commandlist" "r"} commands] {         puts stderr "$cr$commands$ce\n"         exit 1     }     log_file -noappend -a "$hostshort.txt"          spawn telnet $hostname         expect \             {             "sername:" {}             "ogin:" {}             "assword:" {send -s "\r"                              expect \                                 {                                 "ogin:" {}                                 "sername:" {}                                 }                 }             timeout {                 send_user "timed out on device $hostshort logon.\n"                 break             }         }          send -s "myuserid\r"         expect {             "assword:" {}             timeout {                 send_user "timed out on device $hostshort logon.\n"                 break             }         }          send -s "mypassword\r"         expect {             "$hostshort" {}             timeout {                 send_user "timed out on device $hostshort logon.\n"                 break             }         }          while {[gets $commands command] >= 0} {             send -s "$command\r"             expect {                 "$hostshort#" {}                 timeout {send_user "timed out waiting $hostshort # prompt.\n"}             }          }     send -s "exit\r" log_file }  close $switches close $commands 

i typically use switchlist.txt file looks this:

switch1.domainname.com switch2.domainname.com 

i use file called commands.txt lists commands this:

show interface status sh run 

the script executed via

# ./get-stuff.exp switchlist.txt commands.txt 

i suspect may running out of (something) not closing spawned processes inside loop. try replacing contents of loop this:

spawn telnet $hostname expect {     "sername:" { send -s "$myuserid\r"; exp_continue }     "assword:" { send -s "mypassword\r"; exp_continue }     timeout {         send_user "timed out on device $hostshort logon.\n"         continue   ;# next host     }     "$hostshort" }  while {[gets $commands command] >= 0} {     send -s "$command\r"     expect {         "$hostshort#" {}         timeout {             send_user "timed out waiting $hostshort # prompt.\n"             continue   ;# next host         }     }  } send -s "exit\r" expect eof wait  exp_close