CMUNIQUE_ID Name
CMUNIQUE_ID Author
Craig B. Markwardt, NASA/GSFC Code 662, Greenbelt, MD 20770
craigm@lheamail.gsfc.nasa.gov Purpose
Return a unique ID string Calling Sequence
ID = CMUNIQUE_ID([STRINGVAL])
Description
CMUNIQUE_ID returns a "unique" 8 character identifier.
Programmers can use this routine to derive unique strings which
can be used to write files, etc.
Identifiers are "unique" in the sense that it is unlikely that two
identifiers in a given IDL session will coincide. Thus the
identifier is useful for constructing temporary filenames and
other hash values. User routines are encouraged to append other
identifying information to this string, such as a session id, a
hostname, or a process id number.
The identifier is computed from various sources of random
information. Users may supply additional information to be
scrambled into the identifier by passing the FODDER parameter.
CMUNIQUE_ID will return a different identifier upon each call,
with or without the FODDER keyword. It maintains an internal
sequence counter, and and also scrambles in the system time.
These practices should ensure that successive identifiers are
different from one another. Inputs
FODDER - Any scalar string value. These values are used to
additionally scramble the identifier.
Keywords
NONE
Returns
The 8-character identifier string. Example
Print two distinct identifiers.
IDL> print, cmunique_id(), ' ', cmunique_id()
29C47600 79061C57 See Also
NONE Modification History
Written, CM, 11 Jan 2001