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diff --git a/misc-utils/uuidgen.1 b/misc-utils/uuidgen.1 new file mode 100644 index 0000000..75fef5d --- /dev/null +++ b/misc-utils/uuidgen.1 @@ -0,0 +1,102 @@ +.\" Copyright 1999 Andreas Dilger (adilger@enel.ucalgary.ca) +.\" +.\" This file may be copied under the terms of the GNU Public License. +.TH UUIDGEN 1 "June 2011" "util-linux" "User Commands" +.SH NAME +uuidgen \- create a new UUID value +.SH SYNOPSIS +.B uuidgen +[options] +.SH DESCRIPTION +The +.B uuidgen +program creates (and prints) +a new universally unique identifier (UUID) using the +.BR libuuid (3) +library. The new UUID can reasonably be considered unique among +all UUIDs created on the local system, +and among UUIDs created on other systems in the past +and in the future. +.PP +There are three types of UUIDs which +.B uuidgen +can generate: time-based UUIDs, random-based UUIDs, and hash-based UUIDs. +By default +.B uuidgen +will generate a random-based UUID if a high-quality random number +generator is present. Otherwise, it will choose a time-based UUID. +It is possible to force the generation of one of these first two +UUID types by using the +.B \-\-random +or +.B \-\-time +options. +.PP +The third type of UUID is generated with the +.B \-\-md5 +or +.B \-\-sha1 +options, followed by +\fB\-\-namespace\fR \fInamespace\fR +and +\fB\-\-name\fR \fIname\fR. +The \fInamespace\fR may either be a well-known UUID, or else +an alias to one of the well-known UUIDs defined in RFC 4122, that is +.BR @dns , +.BR @url , +.BR @oid , +or +.BR @x500 . +The \fIname\fR is an arbitrary string value. The generated UUID is the +digest of the concatenation of the namespace UUID and the name value, hashed +with the MD5 or SHA1 algorithms. It is, therefore, a predictable value +which may be useful when UUIDs are being used as handles or nonces for +more complex values or values which shouldn't be disclosed directly. +See the RFC for more information. +.SH OPTIONS +.TP +.BR \-r , " \-\-random" +Generate a random-based UUID. This method creates a UUID consisting mostly +of random bits. It requires that the operating system have a high +quality random number generator, such as +.IR /dev/random . +.TP +.BR \-t , " \-\-time" +Generate a time-based UUID. This method creates a UUID based on the system +clock plus the system's ethernet hardware address, if present. +.TP +.BR \-h , " \-\-help" +Display help text and exit. +.TP +.BR \-V , " \-\-version" +Display version information and exit. +.TP +.BR \-m , " \-\-md5" +Use MD5 as the hash algorithm. +.TP +.BR \-s , " \-\-sha1" +Use SHA1 as the hash algorithm. +.TP +.BR \-n , " \-\-namespace " \fInamespace\fP +Generate the hash with the \fInamespace\fP prefix. The \fInamespace\fP is UUID, +or '@ns' where "ns" is well-known predefined UUID addressed by namespace name +(see above). +.TP +.BR \-N , " \-\-name " \fIname\fR +Generate the hash of the \fIname\fR. +.TP +.BR \-x , " \-\-hex" +Interpret name \fIname\fR as a hexadecimal string. +.SH "CONFORMING TO" +OSF DCE 1.1 +.SH EXAMPLES +uuidgen \-\-sha1 \-\-namespace @dns \-\-name "www.example.com" +.SH AUTHOR +.B uuidgen +was written by Andreas Dilger for libuuid. +.SH SEE ALSO +.BR libuuid (3), +.B "RFC 4122" +.SH AVAILABILITY +The uuidgen command is part of the util-linux package and is available from +https://www.kernel.org/pub/linux/utils/util-linux/. |