Scheduled Maintenance Window

When you use 'clock format' using %k (without the leading zero for the hour field) it pads single digit hours with a space. This extra space generates an empty list element when passed to split and causes the TCL error about a null length string.

Rule snippet showing the problem:

 
    log local0. "Clock output: [clock format [clock seconds] -format {%A %k %M}], \$k: $k"  
    set k [split [clock format [clock seconds] -format {%A %k %M}] " "] 
    log local0. "\$k split output llength: [llength $k]" 
 

Log output:

Clock output: Thursday 9 05, $k: Thursday {} 9 05

$k split output llength: 4

Rule snippet:

 
    log local0. "Clock output: [clock format [clock seconds] -format {%A %H %M}], \$H: $H"  
    set H [split [clock format [clock seconds] -format {%A %H %M}] " "] 
    log local0. "\$H split output llength: [llength $H]" 
 

Log output:

Clock output: Thursday 09 05, $H: Thursday 09 05

$H split output llength: 3

You can work around this by using scan to parse the day, hour and minute regardless of the spaces:

 
     Get time in seconds, formatted as day of week (%A) hour (%k) minute (%M) 
     Use scan to save output as $cur_day $cur_hour $cur_minute 
    scan [clock format [clock seconds] -format {%A %k %M}] {%s %d %d} cur_day cur_hour cur_minute 
    set cur_time ${cur_hour}${cur_minute} 
 

So this example should work. In a simple test if the cur_time is 600 the comparison 600 >= 0600 is true. Though I haven't tested the rule completely.

 
 when HTTP_REQUEST { 
  
     Change the following to set schedule 
    set maintenance_start_time "0200"; 
    set maintenance_end_time "0600"; 
    set maintenance_day "Saturday"; 
  
     Get time in seconds, formatted as day of week (%A) hour (%k) minute (%M) 
     Use scan to save output as $cur_day $cur_hour $cur_minute 
    scan [clock format [clock seconds] -format {%A %k %M}] {%s %d %d} cur_day cur_hour cur_minute 
    set cur_time ${cur_hour}${cur_minute} 
  
    log local0. "\$cur_day: $cur_day, \$cur_hour: $cur_hour, \$cur_minute: $cur_minute, \$cur_time: $cur_time" 
  
    if { ($cur_day eq $maintenance_day) && 
       ($cur_time >= $maintenance_start_time) && 
       ($cur_time <= $maintenance_end_time) } { 
       HTTP::respond "Maintenance message" 
       log local0. "Maintenance message" 
    } 
 } 
 

Aaron