.TH CIDR 1
.SH NAME
cidr \- search files for ip address patterns
.SH SYNOPSIS
.B ip/cidr
[
.B -cLlnrsv
]
.I pattern
|
[
.B -f
.I patternfile
]
.I file
...
.SH DESCRIPTION
.I Cidr
is analogous to
.IR grep (1)
for IP addresses.
The input is searched
for tokens that match the
.IR pattern ,
a set of whitespace-seperated CIDRs or CIDRs
negated with '~'.
The options are
.TP
.B -c
Print only a count of matching lines.
.PD 0
.TP
.B -l
(ell) Print the names of files with selected lines; don't print the lines.
.TP
.B -L
Print the names of files with no selected lines;
the converse of
.BR -l .
.TP
.B -n
Mark each printed line with its line number counted in its file.
.TP
.B -r
Reverse the meaning of the pattern and tokens.
.TP
.B -s
Produce no output, but return status.
.TP
.B -v
Reverse: print lines that do not match the pattern.
.TP
.B -f
The pattern argument is the name of a file containing regular
expressions one per line.
.PD
.PP
The format of the pattern is standard
CIDR notation.  A
.L ~
may prefix the CIDR to negate the match.
These are all legal patterns
.IP
.EX
10.220.0.1
10.220.0.1/18
~fc00::/7
.EE
.PP
See
.B /lib/badcidr
for a list of RFC3330 unroutable or illegal CIDRs.
.SH SOURCE
.B /sys/src/cmd/ip/cidr.c
.SH "SEE ALSO"
.B /lib/rfc/rfc3330
.SH BUGS
Combinations of
.BR -v ,
.B -r
and patterns with
.L ~
can be misleading.
.PP
Missing a
.L \&
verb.