Provided by: gawk_5.2.1-2build3_amd64 
NAME
writea, reada, writeall, readall - write and read gawk arrays to/from files
SYNOPSIS
@load "rwarray"
ret = writea(file, array)
ret = reada(file, array)
ret = writeall(file)
ret = readall(file)
DESCRIPTION
The rwarray extension adds functions named writea(), reada(), writeall(), and readall(), 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.
writeall()
This function takes a string argument, which is the name of the file to which dump the state of
all variables. Calling this function is completely equivalent to calling writea() with the second
argument equal to SYMTAB. It returns one on success, or zero upon failure.
readall()
This function takes a string argument, which is the name of the file from which to read the
contents of various global variables. For each variable in the file, the data is loaded unless
the variable already exists. If the variable already exists, the data for that variable in the
file is ignored. It returns one on success, or 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)
...
ret = writeall("globalstate.bin")
...
ret = readall("globalstate.bin")
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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