rwarray - write and read gawk arrays to/from files
@load "rwarray" ret = writea(file, array) ret = reada(file, array)
RWARRAY(3) GNU Awk Extension Modules RWARRAY(3)
NAME
writea, reada - write and read gawk arrays to/from files
SYNOPSIS
@load "rwarray"
ret = writea(file, array)
ret = reada(file, array)
DESCRIPTION
The rwarray extension adds two functions named writea(). and reada(),
as follows.
writea()
This function takes a string argument, which is the name of the
file to which dump the array, and the array itself as the second
argument. writea() understands multidimensional arrays. It
returns one on success, or zero upon failure.
reada()
is the inverse of writea(); it reads the file named as its first
argument, filling in the array named as the second argument. It
clears the array first. Here too, the return value is one on
success and zero upon failure.
ATTRIBUTES
See attributes(7) for descriptions of the following attributes:
+---------------+------------------+
|ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+---------------+------------------+
|Availability | text/gawk |
+---------------+------------------+
|Stability | Volatile |
+---------------+------------------+
NOTES
The array created by reada() is identical to that written by writea()
in the sense that the contents are the same. However, due to implemen-
tation issues, the array traversal order of the recreated array will
likely be different from that of the original array. As array traver-
sal order in AWK is by default undefined, this is not (technically) a
problem. If you need to guarantee a particular traversal order, use
the array sorting features in gawk to do so.
The file contains binary data. All integral values are written in net-
work byte order. However, double precision floating-point values are
written as native binary data. Thus, arrays containing only string
data can theoretically be dumped on systems with one byte order and
restored on systems with a different one, but this has not been tried.
Source code for open source software components in Oracle Solaris can
be found at https://www.oracle.com/downloads/opensource/solaris-source-
code-downloads.html.
This software was built from source available at
https://github.com/oracle/solaris-userland. The original community
source was downloaded from
https://ftp.gnu.org/gnu/gawk/gawk-5.1.1.tar.xz.
Further information about this software can be found on the open source
community website at https://www.gnu.org/software/gawk.
EXAMPLE
@load "rwarray"
...
ret = writea("arraydump.bin", array)
...
ret = reada("arraydump.bin", array)
SEE ALSO
GAWK: Effective AWK Programming, filefuncs(3), fnmatch(3), fork(3),
inplace(3), ordchr(3), readdir(3), readfile(3), revoutput(3), time(3).
AUTHOR
Arnold Robbins, arnold@skeeve.com.
COPYING PERMISSIONS
Copyright (C) 2012, 2013, 2018, Free Software Foundation, Inc.
Permission is granted to make and distribute verbatim copies of this
manual page provided the copyright notice and this permission notice
are preserved on all copies.
Permission is granted to copy and distribute modified versions of this
manual page under the conditions for verbatim copying, provided that
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permission notice identical to this one.
Permission is granted to copy and distribute translations of this man-
ual page into another language, under the above conditions for modified
versions, except that this permission notice may be stated in a trans-
lation approved by the Foundation.
Free Software Foundation Feb 02 2018 RWARRAY(3)