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Doc updates from Darren on char2-16 removal

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This commit is contained in:
Bruce Momjian
1998-04-26 04:18:06 +00:00
parent 0d203b745d
commit d31736e92b
6 changed files with 35 additions and 48 deletions
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35
doc/src/sgml/xfunc.sgml
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@ -136,7 +136,7 @@
AS 'SELECT \'None\'::text AS name,
1000 AS salary,
25 AS age,
\'none\'::char16 AS dept;'
\'none\'::text AS dept;'
LANGUAGE 'sql';
</ProgramListing>
@ -263,7 +263,7 @@ The reason why, in general, we must use the function
<Para>
On the other hand, fixed-length types of any size may
be passed by-reference. For example, here is a sample
implementation of the <ProductName>Postgres</ProductName> char16 type:
implementation of a <ProductName>Postgres</ProductName> type:
<ProgramListing>
/* 16-byte structure, passed by reference */
@ -305,7 +305,6 @@ The reason why, in general, we must use the function
structure, we might use a code fragment like this:
<ProgramListing>
#include "postgres.h"
#include "utils/palloc.h"
...
char buffer[40]; /* our source data */
...
@ -322,20 +321,23 @@ The reason why, in general, we must use the function
Suppose <FileName>funcs.c</FileName> look like:
<ProgramListing>
#include &lt;string.h&gt;
#include "postgres.h" /* for char16, etc. */
#include "utils/palloc.h" /* for palloc */
#include "postgres.h"
int
add_one(int arg)
{
return(arg + 1);
}
char16 *
concat16(char16 *arg1, char16 *arg2)
text *
concat_text(text *arg1, text *arg2)
{
char16 *new_c16 = (char16 *) palloc(sizeof(char16));
memset((void *) new_c16, 0, sizeof(char16));
(void) strncpy(new_c16, arg1, 16);
return (char16 *)(strncat(new_c16, arg2, 16));
int32 new_text_size = VARSIZE(arg1) + VARSIZE(arg2) - VARHDRSZ;
text *new_text = (text *) palloc(new_text_size);
memset((void *) new_text, 0, new_text_size);
VARSIZE(new_text) = new_text_size;
strncpy(VARDATA(new_text), VARDATA(arg1), VARSIZE(arg1)-VARHDRSZ);
strncat(VARDATA(new_text), VARDATA(arg2), VARSIZE(arg2)-VARHDRSZ);
return (new_text);
}
text *
copytext(text *t)
@ -364,7 +366,7 @@ The reason why, in general, we must use the function
CREATE FUNCTION add_one(int4) RETURNS int4
AS 'PGROOT/tutorial/obj/funcs.so' LANGUAGE 'c';
CREATE FUNCTION concat16(char16, char16) RETURNS char16
CREATE FUNCTION concat_text(text, text) RETURNS text
AS 'PGROOT/tutorial/obj/funcs.so' LANGUAGE 'c';
CREATE FUNCTION copytext(text) RETURNS text
@ -401,7 +403,7 @@ The reason why, in general, we must use the function
In the query above, we can define c_overpaid as:
<ProgramListing>
#include "postgres.h" /* for char16, etc. */
#include "postgres.h"
#include "libpq-fe.h" /* for TUPLE */
bool
c_overpaid(TUPLE t,/* the current instance of EMP */
@ -426,7 +428,7 @@ The reason why, in general, we must use the function
is null. <Acronym>GetAttributeByName</Acronym> will align data properly
so you can cast its return value to the desired type.
For example, if you have an attribute name which is of
the type char16, the <Acronym>GetAttributeByName</Acronym> call would look
the type name, the <Acronym>GetAttributeByName</Acronym> call would look
like:
<ProgramListing>
char *str;
@ -517,8 +519,9 @@ Most of the header (include) files for <ProductName>Postgres</ProductName>
</Para>
<ListItem>
<Para> Most of the internal <ProductName>Postgres</ProductName> types are declared
in postgres.h, so it's usually a good idea to
include that file as well.
in postgres.h, so it's a good idea to always
include that file as well. Including postgres.h
will also include elog.h and palloc.h for you.
</Para>
<ListItem>
<Para> Compiling and loading your object code so that