1RWARRAY(3am) GNU Awk Extension Modules RWARRAY(3am)
2
6 writea, reada - write and read gawk arrays to/from files
7
9 @load "rwarray"
10 ret = writea(file, array)
12 ret = reada(file, array)
13
15 The rwarray extension adds two functions named writea(). and reada(),
16 as follows.
17 writea()
19 This function takes a string argument, which is the name of the
20 file to which dump the array, and the array itself as the second
21 argument. writea() understands multidimensional arrays. It
22 returns one on success, or zero upon failure.
23 reada()
25 is the inverse of writea(); it reads the file named as its first
26 argument, filling in the array named as the second argument. It
27 clears the array first. Here too, the return value is one on
28 success and zero upon failure.
29
31 The array created by reada() is identical to that written by writea()
32 in the sense that the contents are the same. However, due to implemen‐
33 tation issues, the array traversal order of the recreated array will
34 likely be different from that of the original array. As array traver‐
35 sal order in AWK is by default undefined, this is not (technically) a
36 problem. If you need to guarantee a particular traversal order, use
37 the array sorting features in gawk to do so.
38 The file contains binary data. All integral values are written in net‐
40 work byte order. However, double precision floating-point values are
41 written as native binary data. Thus, arrays containing only string
42 data can theoretically be dumped on systems with one byte order and
43 restored on systems with a different one, but this has not been tried.
44
46 @load "rwarray"
47 ...
48 ret = writea("arraydump.bin", array)
49 ...
50 ret = reada("arraydump.bin", array)
51
53 GAWK: Effective AWK Programming, filefuncs(3am), fnmatch(3am),
54 fork(3am), inplace(3am), ordchr(3am), readdir(3am), readfile(3am),
55 revoutput(3am), time(3am).
56
58 Arnold Robbins, arnold@skeeve.com.
59
61 Copyright © 2012, 2013, 2018, Free Software Foundation, Inc.
62 Permission is granted to make and distribute verbatim copies of this
64 manual page provided the copyright notice and this permission notice
65 are preserved on all copies.
66 Permission is granted to copy and distribute modified versions of this
68 manual page under the conditions for verbatim copying, provided that
69 the entire resulting derived work is distributed under the terms of a
70 permission notice identical to this one.
71 Permission is granted to copy and distribute translations of this man‐
73 ual page into another language, under the above conditions for modified
74 versions, except that this permission notice may be stated in a trans‐
75 lation approved by the Foundation.
76Free Software Foundation Feb 02 2018 RWARRAY(3am)