problem1: nmap installed to /usr/bin/nmap and in usr's path, but when run ./scan.pl 127.0.0.1, the scan.pl help was triggered there.
problem2: perl scan.pl --nmap /usr/bin/nmap 127.0.0.1, the program returned after 5minutes.
[root@lnx70 tools]# perl scan.pl --nmap /usr/bin/nmap 127.0.0.1
scan.pl - ( http://anthonypersaud.com )
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Using nmap exe: /usr/bin/nmap
>127.0.0.1
[+] Status: (UP)
[+] Hostname(s) :
localhost.localdomain
PORT SERVICE (PRODUCT ) [VERSION ] EXTRA
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[+] UDP Ports :
PORT SERVICE (PRODUCT ) [VERSION ] EXTRA
------------------------------------------------------------
111 rpc ( ) [ ]
PORT SERVICE (PRODUCT ) [VERSION ] EXTRA
------------------------------------------------------------
123 ntp (NTP ) [v4 ]
PORT SERVICE (PRODUCT ) [VERSION ] EXTRA
------------------------------------------------------------
5353 zeroconf ( ) [ ]