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.