RWARRAY
Section: GNU Awk Extension Modules (3am)
Updated: Feb 02 2018
Page Index
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.
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 implementation issues, the array traversal order of the recreated
array will likely be different from that of the original array.
As array traversal 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 network 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.
EXAMPLE
@load "rwarray"
...
ret = writea("arraydump.bin", array)
...
ret = reada("arraydump.bin", array)
SEE ALSO
GAWK: Effective AWK Programming,
filefuncs(3am),
fnmatch(3am),
fork(3am),
inplace(3am),
ordchr(3am),
readdir(3am),
readfile(3am),
revoutput(3am),
time(3am).
AUTHOR
Arnold Robbins,
arnold@skeeve.com.
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