Cfrgtkky

Using bash regular expression matching:

$ f="/foo/bar/baz59_ 99stuff.thing"

$ [[ $f =~ ([0-9]+)([^0-9]+)$ ]]

OK, what do we have now?

$ declare -p BASH_REMATCH

declare -ar BASH_REMATCH=([0]="99stuff.thing" [1]="99" [2]="stuff.thing")

So we can construct the new filename

if [[ $f =~ ([0-9]+)([^0-9]+)$ ]]; then

    prefix=${f%${BASH_REMATCH[0]}}           # remove "99stuff.thing" from $f

    number=$(( 10#${BASH_REMATCH[1]} + 1 ))  # use "10#" to force base10

    new=${prefix}${number}${BASH_REMATCH[2]}

    echo $new

fi

# => /foo/bar/baz59_ 100stuff.thing

With GNU awk for the 3rd arg to match():

$ awk -v t=3 'match($0,/(.*)([0-9]+)([^0-9]*)$/,a) && a[2]>t{a[2]++; $0=a[1] a[2] a[3]} 1' file

/foo/bar/baz59_ 6stuff.thing

Just set t to whatever your threshold value is for incrementing, e.g.:

$ awk -v t=7 'match($0,/(.*)([0-9]+)([^0-9]*)$/,a) && a[2]>t{a[2]++; $0=a[1] a[2] a[3]} 1' file

/foo/bar/baz59_ 5stuff.thing

if it's greater than a script argument.

If I get it correctly(I am assuming you are passing an argument through a script and if its value is greater than string's 2nd field digit then increase 1 into that 2nd field's digit), could you please try following once.

cat script.ksh

value=$1

echo "/foo/bar/baz59_ 5stuff.thing" | 

awk -v arg="$value" '

  match($2,/[0-9]+/){

    val=substr($2,RSTART,RLENGTH)

    val=val<arg?val+1:val

    $2=val substr($2,RSTART+RLENGTH)

}

1'

Here is an example when I run script.ksh it gives following output.

/script.ksh 7

/foo/bar/baz59_ 6stuff.thing

Here is a shorter gnu awk approach:

cat incr.awk

{

   n = split($0, a, /[0-9]+/, b)

   for(i=1; i<n; i++)

      s = s a[i] b[i] + (b[i] < max && i == n-1 ? 1 : 0)

   print s a[i]

}

Then use it as:

awk -v max=80 -f incr.awk <<< '/foo/bar/baz59_ 5stuff.thing'

/foo/bar/baz59_ 6stuff.thing



awk -v max=80 -f incr.awk <<< '/foo/bar/baz59_ 79stuff.thing'

/foo/bar/baz59_ 80stuff.thing





awk -v max=80 -f incr.awk <<< '/foo/bar/baz59_ 90stuff.thing'

/foo/bar/baz59_ 90stuff.thing



awk -v max=80 -f incr.awk <<< '/foo/bar/baz59_ 80stuff.thing'

/foo/bar/baz59_ 80stuff.thing



awk -v max=80 -f incr.awk <<< '/foo/bar/stuff.thing'

/foo/bar/stuff.thing

An awk:

$ echo /foo/bar/baz59_ 99stuff.thing |

awk '

/[0-9]/ {

    rstart=1                                    # keep track of the start

    while(match(substr($0,rstart),/[0-9]+/)) {  # while numbers last

        rstart+=RSTART+RLENGTH-1                # increase rstart

        rlength=RLENGTH                         # remember length too

    }

    v=substr($0,rstart-rlength,rlength)+1                    # increase last number

    print substr($0,1,rstart-rlength-1) v substr($0,rstart)  # print in parts

    next

}1'                                             # in case there was no number

/foo/bar/baz59_ 100stuff.thing

Edit:

Whoops, I missed the argument requirement (increase the last number - - by a one, if it's greater than a script argument):

$ echo /foo/bar/baz59_ 99stuff.thing |

awk -v arg=100 '

/[0-9]/ {

    rstart=1

    while(match(substr($0,rstart),/[0-9]+/)) {

        rstart+=RSTART+RLENGTH-1

        rlength=RLENGTH

    }

    v=substr($0,rstart-rlength,rlength)

    if(0+v>arg) {                           # test if v greater that argument

        print substr($0,1,rstart-rlength-1) v+1 substr($0,rstart)

        next

    }

}1'

Output now:

/foo/bar/baz59_ 99stuff.thing