NAME
yexpand - tool to expand environment variables in Nypatchy cradles
SYNOPSIS
yexpand inputfile [ outputfile ]
DESCRIPTION
yexpand is a very simple script to expand environment variables in a
text file to their current values in the shell environment. It was
written to be used with nypatchy cradles. It is recommended you not
try to use it for any other purposes (note BUGS below).
USAGE
yexpand takes inputfile as input, replaces all instances of shell
variables (in the form $VARIABLE or ${VARIABLE}) with their current
values in the environment, and saves the result to outputfile.
Undefined variables are replaced with the empty string. If outputfile
is not given, the result is instead saved to the current directory as a
file of the same name as inputfile. Thus an input file in the current
directory will be overwritten.
BUGS
This script is very simple-minded. Since it basically just echos its
input file as a here-doc, it will attempt to perform all types of shell
substitution (command substitution, etc.) as well as variable
substitution. Hence it is likely to fail on anything except the very
simplest text files.
Additionally, this script creates a temporary file. The file is
created in the current directory, so there should not be security
implications. However, any existing file named file.yexp (where file
is the basename of inputfile) in the current directory will be
overwritten and then deleted.
SEE ALSO
fcasplit(1), nycheck(1), nydiff(1), nyindex(1), nylist(1), nymerge(1),
nypatchy(1), nyshell(1), nysynopt(1), nytidy(1)
The reference manual for the Nypatchy suite of programs is available in
compressed PostScript format at the following URL:
http://wwwasdoc.web.cern.ch/wwwasdoc/psdir/p5refman.ps.gz
AUTHOR
This manual page was written by Kevin McCarty <kmccarty@debian.org> for
the Debian GNU/Linux system (but may be used by others). It is
licensed under the GNU General Public License, version 2 or later (at
your choice).
COPYRIGHT
Copyright (C) Kevin B. McCarty, 2008.
Mar 12, 2008