Mac address has a specific format.And your regex does not validate it correctly.It vaildates too many other strings as well.See d link i posted.They are no mac addresses but still get parsed – vks Nov 13 '14 at 4:28. 4.3 selecting lines by text matching. GNU sed supports the following regular expression addresses. The default regular expression is Basic Regular Expression (BRE).If -E or -r options are used, The regular expression should be in Extended Regular Expression (ERE) syntax. /regexp/ This will select any line which matches the regular expression regexp.
Post #1,000 on this blog. Fitting that it’s Python nerd shit, huh?
I needed a way to search for MAC addresses, which are unique identifiers for networking hardware. For example, if your computer has a built-in Ethernet port, as well as wireless capability, then it has 2 MAC addresses. These are always 6 groups of 2 hexadecimal characters (0 through 9, and A through F). E.g., a valid MAC address would be: 01:98:DF:9E:10:37. Theoretically, every MAC address on every computer in the world will be unique, as the naming scheme provides over 281 trillion possible combinations (281,474,976,710,656).
Canonically these groups of 2 hex digits are separated by a colon, but many people record them with hyphens instead. So I needed to search for this particular pattern of characters amid a potentially-vast amount of text. Enter regular expressions (which I totally suck at using).
The regex I came up with is:
Going through it, piece by piece:
[a-fA-F0-9] = find any character A-F, upper and lower case, as well as any number
[a-fA-F0-9]{2} = find that twice in a row
[a-fA-F0-9]{2}[:|-] = followed by either a “:” or a “-” character (the backslash escapes the hyphen, since the hyphen itself is a valid metacharacter for that type of expression; this tells the regex to look for the hyphen character, and ignore its role as an operator in this piece of the expression)
[a-fA-F0-9]{2}[:|-]? = make that final “:” or “-” character optional; since the last pair of characters won’t be followed by anything, and we want them to be included, too; that’s a chunk of 2 or 3 characters, so far
([a-fA-F0-9]{2}[:|-]?){6} = find this type of chunk 6 times in a row
Let’s give it a shot.
First, a list of strings… e.g., a row from a comma-delimited file (returned via the csv module):
Run it:
Next, a string:
Run it:
Fuckin’ bickety-bam, the whole stage comes crashing down.
- DESCRIPTION
Regexp::Common::net -- provide regexes for IPv4, IPv6, and MAC addresses.
Please consult the manual of Regexp::Common for a general description of the works of this interface.
Do not use this module directly, but load it via Regexp::Common.
This modules gives you regular expressions for various style IPv4, IPv6, and MAC (or ethernet) addresses.
$RE{net}{IPv4}
Returns a pattern that matches a valid IP address in 'dotted decimal'. Note that while 318.99.183.11 is not a valid IP address, it does match /$RE{net}{IPv4}/, but this is because 318.99.183.11 contains a valid IP address, namely 18.99.183.11. To prevent the unwanted matching, one needs to anchor the regexp: /^$RE{net}{IPv4}$/.
For this pattern and the next four, under -keep (See Regexp::Common):
captures the entire match
captures the first component of the address
captures the second component of the address
captures the third component of the address
captures the final component of the address
$RE{net}{IPv4}{dec}{-sep}
Returns a pattern that matches a valid IP address in 'dotted decimal'. Leading 0s are allowed, as long as each component does not exceed 3 digits.
If -sep=P is specified the pattern P is used as the separator. By default P is qr/[.]/.
$RE{net}{IPv4}{strict}{-sep}
Returns a pattern that matches a valid IP address in 'dotted decimal', but disallow any leading 0s.
If -sep=P is specified the pattern P is used as the separator. By default P is qr/[.]/.
$RE{net}{IPv4}{hex}{-sep}
Returns a pattern that matches a valid IP address in 'dotted hexadecimal', with the letters A to F capitalized.
If -sep=P is specified the pattern P is used as the separator. By default P is qr/[.]/. -sep=' and -sep=' ' are useful alternatives.
$RE{net}{IPv4}{oct}{-sep}
Returns a pattern that matches a valid IP address in 'dotted octal'
If -sep=P is specified the pattern P is used as the separator. By default P is qr/[.]/.
$RE{net}{IPv4}{bin}{-sep}
Returns a pattern that matches a valid IP address in 'dotted binary'
If -sep=P is specified the pattern P is used as the separator. By default P is qr/[.]/.
$RE{net}{MAC}
Returns a pattern that matches a valid MAC or ethernet address as colon separated hexadecimals.
For this pattern, and the next four, under -keep (See Regexp::Common):
captures the entire match
captures the first component of the address
captures the second component of the address
captures the third component of the address
captures the fourth component of the address
captures the fifth component of the address
captures the sixth and final component of the address
This pattern, and the next four, have a subs method as well, which will transform a matching MAC address into so called canonical format. Canonical format means that every component of the address will be exactly two hexadecimals (with a leading zero if necessary), and the components will be separated by a colon.
$RE{net}{MAC}{dec}{-sep}
Returns a pattern that matches a valid MAC address as colon separated decimals.
If -sep=P is specified the pattern P is used as the separator. By default P is qr/:/.
$RE{net}{MAC}{hex}{-sep}
Returns a pattern that matches a valid MAC address as colon separated hexadecimals, with the letters a to f in lower case.
If -sep=P is specified the pattern P is used as the separator. By default P is qr/:/.
$RE{net}{MAC}{oct}{-sep}
Returns a pattern that matches a valid MAC address as colon separated octals.
If -sep=P is specified the pattern P is used as the separator. By default P is qr/:/.
$RE{net}{MAC}{bin}{-sep}
Returns a pattern that matches a valid MAC address as colon separated binary numbers.
If -sep=P is specified the pattern P is used as the separator. By default P is qr/:/.
$RE{net}{IPv6}{-sep => ':'}{-style => 'HeX'}
Returns a pattern matching IPv6 numbers. An IPv6 address consists of eight groups of four hexadecimal digits, separated by colons. In each group, leading zeros may be omitted. Two or more consecutive groups consisting of only zeros may be omitted (including any colons separating them), resulting into two sets of groups, separated by a double colon. (Each of the groups may be empty; :: is a valid address, equal to 0000:0000:0000:0000:0000:0000:0000:0000). The hex numbers may be in either case.
If the -sep option is used, its argument is a pattern that matches the separator that separates groups. This defaults to :. The -style option is used to denote which case the hex numbers may be. The default style, 'HeX' indicates both lower case letters 'a' to 'f' and upper case letters 'A' to 'F' will be matched. The style 'HEX' restricts matching to upper case letters, and 'hex' only matches lower case letters.
If {-keep} is used, $1 to $9 will be set. $1 will be set to the matched address, while $2 to $9 will be set to each matched group. If a group is omitted because it contains all zeros, its matching variable will be the empty string.
Example:
Perl 5.10 (or later) is required for this pattern.
$RE{net}{domain}
Regex Get Mac Address
Returns a pattern to match domains (and hosts) as defined in RFC 1035. Under I{-keep} only the entire domain name is returned.
RFC 1035 says that a single space can be a domainname too. So, the pattern returned by $RE{net}{domain} recognizes a single space as well. This is not always what people want. If you want to recognize domainnames, but not a space, you can do one of two things, either use
or use the {-nospace} option (without an argument).
RFC 1035 does not allow host or domain names to start with a digits; however, this restriction is relaxed in RFC 1101; this RFC allows host and domain names to start with a digit, as long as the first part of a domain does not look like an IP address. If the {-rfc1101} option is given (as in $RE {net} {domain} {-rfc1101}), we will match using the relaxed rules.
Mockapetris, P.: DOMAIN NAMES - IMPLEMENTATION AND SPECIFICATION. November 1987.
Mockapetris, P.: DNS Encoding of Network Names and Other Types. April 1987.
Regexp::Common for a general description of how to use this interface.
Damian Conway damian@conway.org.
This package is maintained by Abigail (regexp-common@abigail.be).
Bound to be plenty.
For a start, there are many common regexes missing. Send them in to regexp-common@abigail.be.
This software is Copyright (c) 2001 - 2017, Damian Conway and Abigail.
This module is free software, and maybe used under any of the following licenses:
To install Regexp::Common::net, copy and paste the appropriate command in to your terminal.
Valid Mac Address Format
For more information on module installation, please visit the detailed CPAN module installation guide.