Tail.vbs borrows shamelessy from unix’ tail command, and more or less performs the same function: to obtain the last N lines of a textfile (the tail).
Usage 1 (content is obtained from the filename given on the commandline):
[cscript] TAIL[.vbs] path+filename startline [numberlines]
where ‘startline’ is counted from the end of the file, and numberlines is how many lines to obtain after that point, and defaults to “through end-of-file”
If your filename happens to be a number, be sure to include a full or relative path in front of it so it will be interpreted as a filename. F/e, if you have a file called 6, or 3.2, refer to it like: .\3.2 or c:\x\6
Usage 2 (content is obtained through the pipe)
… | CSCRIPT TAIL.VBS startline [numberlines]
Same idea, but CSCRIPT must be used to launch the vbs, it will not run implicitly.
testfile:
3 from end
2 from end
1 from end
examples:
tail testfile 3 1 == 3 from end
tail testfile 3 == 3 from end [crlf]2 from end[crlf]1 from end
tail testfile 1 == 1 from end
type testfile | cscript tail.vbs 3 1 == 3 from end
'======== begin vbscript "tail"
set fso=createobject("scripting.filesystemobject")
argcnt=wscript.arguments.count
if argcnt>0 then file=wscript.arguments(0)
if argcnt>1 then tail=wscript.arguments(1)+1
tailend=0
select case argcnt
case 1
'one arg, only interp as line number, use stdin as file
if not isnumeric(file) then wscript.quit
b=""
on error resume next
b=wscript.stdin.readall
if b="" then wscript.quit
tail=file+1
case 2
'two args: file and line, or two lines and stdin for file
if isnumeric(file) then 'two numbers
b=""
on error resume next
b=wscript.stdin.readall
if b="" then wscript.quit
tail=file+1
tailend=tail-wscript.arguments(1)
else
set a=fso.opentextfile(file,1) 'non-number, use as file
b=a.readall
end if
case 3
'easiest: file, line1, line2
tailend=tail-wscript.arguments(2)
set a=fso.opentextfile(file,1)
b=a.readall
end select
p=-1
for i=1 to tail
if i=tailend+1 then p2=p
p=instrrev(b,vbcrlf,p)
if p=0 then
p=1
exit for
end if
next
if p2>0 then c=mid(b,p,p2-p) else c=mid(b,p)
wscript.echo mid(c,3)
'======= end vbscript
