.TH replace "" "" "/rdb Command"
.PC "Insert a record into a file at specified location"
\fBreplace [\-a] [\-m[bhirs] \fItableorlist from to \fB[\fIxfrom xto\fB] < \fIintableorlist\fR
.PP
.II row^replace
The command
.B replace
replaces the row at offsets
.I from
through
.I to
in
.I tableorlist
with the contents of
.IR intableorlist .
.B replace
will not insert a record larger than
.I to
minus
.IR from .
It adds spaces to the
.I last
column of records within
.I tableorlist
that are smaller than the input record.
.PP
.I xfrom
and
.I xto
give the beginning and end of the offsets of the index entry within
.IR tableorlist 's
associated fast-access table, should there be one.
.PP
To obtain painlessly the offsets of the record and its index entry, use
the command
.BR seek .
This is demonstrated in the following example.
.PP
The command
.B update
remembers the location and size of the record it takes out of a file
and passes it to
.B replace
so that only a correctly sized file goes back into that file.
.SH Options
.B replace
recognizes the following options:
.IP \fB\-a\fR
Do not append the record in
.I intableorlist
to the end of
.IR tableorlist .
The default to append if the record is too big
to fit back into the location from which it was taken.
This option allows you to prevent appending.
If you want a binary file to stay
sorted, you will either have to resort it or not allow appending.
.IP \fB\-m[bhirs]\fR
Fast access methods.
See the manual page for
.B index
for a description of what each of these options means.
.SH Example
If table
.B recordtable
contains one record, you use can insert that record into table
.B bigfile
with the following command:
.DM
	replace bigfile 1421 1487 0 8 < recordtable
.DE
.PP
Note that the contents of
.B recordtable
replace rows 1421 through 1487 within
.BR bigfile .
.PP
For the second example, consider again table
.BR inventory ,
as follows:
.DM
Item    Amount  Cost    Value   Description   
----    ------  ----    -----   --------------
   1         3    50      150   rubber gloves
   2       100     5      500   test tubes
   3         5    80      400   clamps
   4        23    19      437   plates
   5        99    24     2376   cleaning cloth
   6        89   147    13083   bunsen burners
   7         5   175      875   scales
.DE
.PP
First, let's use the command
.B seek
to extract a record, and save its offset in the shell variable
.BR LOCATION :
.DM
	LOCATION=`echo 5 | seek -mr -o tmpfile inventory Item`
.DE
.PP
.B $LOCATION
is initialized to the following
.DM
	207 245 54 62
.DE
.PP
and
.B tmpfile
contains the following:
.DM
Item    Amount  Cost    Value   Description   
----    ------  ----    -----   --------------
   5        99    24     2376   cleaning cloth
.DE
.PP
Here we use the record fast-access method.
.PP
Now let's
change 99 to 199 within
.BR tmpfile ,
so we can see a change:
.DM
Item    Amount  Cost    Value   Description   
----    ------  ----    -----   --------------
   5       199    24     2376   cleaning cloth
.DE
.PP
Now we can replace the edited record in
.BR inventory :
.DM
	replace -mr inventory $LOCATION < tmpfile
.DE
.PP
.B inventory
now appears as follows:
.DM
Item    Amount  Cost    Value   Description   
----    ------  ----    -----   --------------
   1         3    50      150   rubber gloves
   2       100     5      500   test tubes
   3         5    80      400   clamps
   4        23    19      437   plates
   5       199    24     2376   cleaning cloth
   6        89   147    13083   bunsen burners
   7         5   175      875   scales
.DE
.PP
You can see that row 5 has been updated, because it now has
199 in it.
.SH "See Also"
.B
seek,
update
.R