Hello I have a range of servers which have a 3-digit identifier in their name (refer to input file below). Not all of the numeric range is use i.e. the following do not exist: serv103 serv109 $cat input serv101 serv102 serv104 serv105 serv106 serv107 serv108 serv110 I am attempting to write a script to identify the 3-digit identifiers NOT in use. Desired output: 101:serv101 102:serv102 103:FREE 104:serv104 105:serv105 106:serv106 107:serv107 108:serv108 109:FREE 110:serv110 My attempt so far has failed to print the free identifier and text "FREE". I'm having problems with the else statement say for instance when id=103 or 109 for i in `cat id` # range from 101-110 do awk -v id=$1 '{ num=sprintf("%s, substr($1,length($1)-2)) if(id==num) { printf("%s%s%s\n", id,":",$1) } }' input Can anyone assist or perhaps suggest a better approach?

Would a batch file be suitable for you? I can suggest an easy solution using a bat.

Unfortunately I have been asked to complete the task in awk

Since my OS is Solaris, I'm using nawk. Also, there is no need to use sprintf: #!/bin/ksh while read line do nawk -v id=$line ' BEGIN { xfree=0 } { num=substr($1,length($1)-2) if(id == num) { printf("%s:%s\n", id,$1) xfree=1 } } END { if(xfree == 0) printf("%s:FREE\n", id) } ' input done < id

nails, Great - that did the job. Thanks for the post.

Thank you user57, but I couldn't let this one go. This is a good example for using awk's associative arrays. I read the input file completely into an array and processed the id file in the main processing loop: nawk ' BEGIN { while ( getline < "input" > 0 ) { num=substr($1,length($1)-2) arr[num]=$1 } } { if($1 in arr) printf("%s:%s\n", $1, arr[$1]) else printf("%s:FREE\n", $1) } ' id

nails, Having already done the job I have just viewed your further post using awk's associative array. An impressive solution! Once again thanks for taking the time to rely nails.