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>Chapter 33. <SPAN
CLASS="APPLICATION"
>ECPG</SPAN
> - Embedded <ACRONYM
CLASS="ACRONYM"
>SQL</ACRONYM
> in C</TD
><TD
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><DIV
CLASS="SECT1"
><H1
CLASS="SECT1"
><A
NAME="ECPG-INFORMIX-COMPAT"
>33.15. <SPAN
CLASS="PRODUCTNAME"
>Informix</SPAN
> Compatibility Mode</A
></H1
><P
> <TT
CLASS="COMMAND"
>ecpg</TT
> can be run in a so-called <I
CLASS="FIRSTTERM"
>Informix compatibility mode</I
>. If
this mode is active, it tries to behave as if it were the <SPAN
CLASS="PRODUCTNAME"
>Informix</SPAN
>
precompiler for <SPAN
CLASS="PRODUCTNAME"
>Informix</SPAN
> E/SQL. Generally spoken this will allow you to use
the dollar sign instead of the <TT
CLASS="LITERAL"
>EXEC SQL</TT
> primitive to introduce
embedded SQL commands:
</P><PRE
CLASS="PROGRAMLISTING"
>$int j = 3;
$CONNECT TO :dbname;
$CREATE TABLE test(i INT PRIMARY KEY, j INT);
$INSERT INTO test(i, j) VALUES (7, :j);
$COMMIT;</PRE
><P>
</P
><DIV
CLASS="NOTE"
><BLOCKQUOTE
CLASS="NOTE"
><P
><B
>Note: </B
> There must not be any white space between the <TT
CLASS="LITERAL"
>$</TT
>
and a following preprocessor directive, that is,
<TT
CLASS="LITERAL"
>include</TT
>, <TT
CLASS="LITERAL"
>define</TT
>, <TT
CLASS="LITERAL"
>ifdef</TT
>,
etc. Otherwise, the preprocessor will parse the token as a host
variable.
</P
></BLOCKQUOTE
></DIV
><P
> There are two compatibility modes: <TT
CLASS="LITERAL"
>INFORMIX</TT
>, <TT
CLASS="LITERAL"
>INFORMIX_SE</TT
>
</P
><P
> When linking programs that use this compatibility mode, remember to link
against <TT
CLASS="LITERAL"
>libcompat</TT
> that is shipped with ECPG.
</P
><P
> Besides the previously explained syntactic sugar, the <SPAN
CLASS="PRODUCTNAME"
>Informix</SPAN
> compatibility
mode ports some functions for input, output and transformation of data as
well as embedded SQL statements known from E/SQL to ECPG.
</P
><P
> <SPAN
CLASS="PRODUCTNAME"
>Informix</SPAN
> compatibility mode is closely connected to the pgtypeslib library
of ECPG. pgtypeslib maps SQL data types to data types within the C host
program and most of the additional functions of the <SPAN
CLASS="PRODUCTNAME"
>Informix</SPAN
> compatibility
mode allow you to operate on those C host program types. Note however that
the extent of the compatibility is limited. It does not try to copy <SPAN
CLASS="PRODUCTNAME"
>Informix</SPAN
>
behavior; it allows you to do more or less the same operations and gives
you functions that have the same name and the same basic behavior but it is
no drop-in replacement if you are using <SPAN
CLASS="PRODUCTNAME"
>Informix</SPAN
> at the moment. Moreover,
some of the data types are different. For example,
<SPAN
CLASS="PRODUCTNAME"
>PostgreSQL's</SPAN
> datetime and interval types do not
know about ranges like for example <TT
CLASS="LITERAL"
>YEAR TO MINUTE</TT
> so you won't
find support in ECPG for that either.
</P
><DIV
CLASS="SECT2"
><H2
CLASS="SECT2"
><A
NAME="ECPG-INFORMIX-TYPES"
>33.15.1. Additional Types</A
></H2
><P
> The Informix-special "string" pseudo-type for storing right-trimmed character string data is now
supported in Informix-mode without using <TT
CLASS="LITERAL"
>typedef</TT
>. In fact, in Informix-mode,
ECPG refuses to process source files that contain <TT
CLASS="LITERAL"
>typedef sometype string;</TT
>
</P><PRE
CLASS="PROGRAMLISTING"
>EXEC SQL BEGIN DECLARE SECTION;
string userid; /* this variable will contain trimmed data */
EXEC SQL END DECLARE SECTION;
EXEC SQL FETCH MYCUR INTO :userid;</PRE
><P>
</P
></DIV
><DIV
CLASS="SECT2"
><H2
CLASS="SECT2"
><A
NAME="ECPG-INFORMIX-STATEMENTS"
>33.15.2. Additional/Missing Embedded SQL Statements</A
></H2
><P
> <P
></P
></P><DIV
CLASS="VARIABLELIST"
><DL
><DT
><TT
CLASS="LITERAL"
>CLOSE DATABASE</TT
></DT
><DD
><P
> This statement closes the current connection. In fact, this is a
synonym for ECPG's <TT
CLASS="LITERAL"
>DISCONNECT CURRENT</TT
>:
</P><PRE
CLASS="PROGRAMLISTING"
>$CLOSE DATABASE; /* close the current connection */
EXEC SQL CLOSE DATABASE;</PRE
><P>
</P
></DD
><DT
><TT
CLASS="LITERAL"
>FREE cursor_name</TT
></DT
><DD
><P
> Due to the differences how ECPG works compared to Informix's ESQL/C (i.e. which steps
are purely grammar transformations and which steps rely on the underlying run-time library)
there is no <TT
CLASS="LITERAL"
>FREE cursor_name</TT
> statement in ECPG. This is because in ECPG,
<TT
CLASS="LITERAL"
>DECLARE CURSOR</TT
> doesn't translate to a function call into
the run-time library that uses to the cursor name. This means that there's no run-time
bookkeeping of SQL cursors in the ECPG run-time library, only in the PostgreSQL server.
</P
></DD
><DT
><TT
CLASS="LITERAL"
>FREE statement_name</TT
></DT
><DD
><P
> <TT
CLASS="LITERAL"
>FREE statement_name</TT
> is a synonym for <TT
CLASS="LITERAL"
>DEALLOCATE PREPARE statement_name</TT
>.
</P
></DD
></DL
></DIV
><P>
</P
></DIV
><DIV
CLASS="SECT2"
><H2
CLASS="SECT2"
><A
NAME="ECPG-INFORMIX-SQLDA"
>33.15.3. Informix-compatible SQLDA Descriptor Areas</A
></H2
><P
> Informix-compatible mode supports a different structure than the one described in
<A
HREF="ecpg-descriptors.html#ECPG-SQLDA-DESCRIPTORS"
>Section 33.7.2</A
>. See below:
</P><PRE
CLASS="PROGRAMLISTING"
>struct sqlvar_compat
{
short sqltype;
int sqllen;
char *sqldata;
short *sqlind;
char *sqlname;
char *sqlformat;
short sqlitype;
short sqlilen;
char *sqlidata;
int sqlxid;
char *sqltypename;
short sqltypelen;
short sqlownerlen;
short sqlsourcetype;
char *sqlownername;
int sqlsourceid;
char *sqlilongdata;
int sqlflags;
void *sqlreserved;
};
struct sqlda_compat
{
short sqld;
struct sqlvar_compat *sqlvar;
char desc_name[19];
short desc_occ;
struct sqlda_compat *desc_next;
void *reserved;
};
typedef struct sqlvar_compat sqlvar_t;
typedef struct sqlda_compat sqlda_t;</PRE
><P>
</P
><P
> The global properties are:
<P
></P
></P><DIV
CLASS="VARIABLELIST"
><DL
><DT
><TT
CLASS="LITERAL"
>sqld</TT
></DT
><DD
><P
> The number of fields in the <TT
CLASS="LITERAL"
>SQLDA</TT
> descriptor.
</P
></DD
><DT
><TT
CLASS="LITERAL"
>sqlvar</TT
></DT
><DD
><P
> Pointer to the per-field properties.
</P
></DD
><DT
><TT
CLASS="LITERAL"
>desc_name</TT
></DT
><DD
><P
> Unused, filled with zero-bytes.
</P
></DD
><DT
><TT
CLASS="LITERAL"
>desc_occ</TT
></DT
><DD
><P
> Size of the allocated structure.
</P
></DD
><DT
><TT
CLASS="LITERAL"
>desc_next</TT
></DT
><DD
><P
> Pointer to the next SQLDA structure if the result set contains more than one record.
</P
></DD
><DT
><TT
CLASS="LITERAL"
>reserved</TT
></DT
><DD
><P
> Unused pointer, contains NULL. Kept for Informix-compatibility.
</P
></DD
></DL
></DIV
><P>
The per-field properties are below, they are stored in the <TT
CLASS="LITERAL"
>sqlvar</TT
> array:
<P
></P
></P><DIV
CLASS="VARIABLELIST"
><DL
><DT
><TT
CLASS="LITERAL"
>sqltype</TT
></DT
><DD
><P
> Type of the field. Constants are in <TT
CLASS="LITERAL"
>sqltypes.h</TT
>
</P
></DD
><DT
><TT
CLASS="LITERAL"
>sqllen</TT
></DT
><DD
><P
> Length of the field data.
</P
></DD
><DT
><TT
CLASS="LITERAL"
>sqldata</TT
></DT
><DD
><P
> Pointer to the field data. The pointer is of <TT
CLASS="LITERAL"
>char *</TT
> type,
the data pointed by it is in a binary format. Example:
</P><PRE
CLASS="PROGRAMLISTING"
>int intval;
switch (sqldata->sqlvar[i].sqltype)
{
case SQLINTEGER:
intval = *(int *)sqldata->sqlvar[i].sqldata;
break;
...
}</PRE
><P>
</P
></DD
><DT
><TT
CLASS="LITERAL"
>sqlind</TT
></DT
><DD
><P
> Pointer to the NULL indicator. If returned by DESCRIBE or FETCH then it's always a valid pointer.
If used as input for <TT
CLASS="LITERAL"
>EXECUTE ... USING sqlda;</TT
> then NULL-pointer value means
that the value for this field is non-NULL. Otherwise a valid pointer and <TT
CLASS="LITERAL"
>sqlitype</TT
>
has to be properly set. Example:
</P><PRE
CLASS="PROGRAMLISTING"
>if (*(int2 *)sqldata->sqlvar[i].sqlind != 0)
printf("value is NULL\n");</PRE
><P>
</P
></DD
><DT
><TT
CLASS="LITERAL"
>sqlname</TT
></DT
><DD
><P
> Name of the field. 0-terminated string.
</P
></DD
><DT
><TT
CLASS="LITERAL"
>sqlformat</TT
></DT
><DD
><P
> Reserved in Informix, value of <CODE
CLASS="FUNCTION"
>PQfformat()</CODE
> for the field.
</P
></DD
><DT
><TT
CLASS="LITERAL"
>sqlitype</TT
></DT
><DD
><P
> Type of the NULL indicator data. It's always SQLSMINT when returning data from the server.
When the <TT
CLASS="LITERAL"
>SQLDA</TT
> is used for a parametrized query, the data is treated
according to the set type.
</P
></DD
><DT
><TT
CLASS="LITERAL"
>sqlilen</TT
></DT
><DD
><P
> Length of the NULL indicator data.
</P
></DD
><DT
><TT
CLASS="LITERAL"
>sqlxid</TT
></DT
><DD
><P
> Extended type of the field, result of <CODE
CLASS="FUNCTION"
>PQftype()</CODE
>.
</P
></DD
><DT
><TT
CLASS="LITERAL"
>sqltypename</TT
><BR><TT
CLASS="LITERAL"
>sqltypelen</TT
><BR><TT
CLASS="LITERAL"
>sqlownerlen</TT
><BR><TT
CLASS="LITERAL"
>sqlsourcetype</TT
><BR><TT
CLASS="LITERAL"
>sqlownername</TT
><BR><TT
CLASS="LITERAL"
>sqlsourceid</TT
><BR><TT
CLASS="LITERAL"
>sqlflags</TT
><BR><TT
CLASS="LITERAL"
>sqlreserved</TT
></DT
><DD
><P
> Unused.
</P
></DD
><DT
><TT
CLASS="LITERAL"
>sqlilongdata</TT
></DT
><DD
><P
> It equals to <TT
CLASS="LITERAL"
>sqldata</TT
> if <TT
CLASS="LITERAL"
>sqllen</TT
> is larger than 32KB.
</P
></DD
></DL
></DIV
><P>
Example:
</P><PRE
CLASS="PROGRAMLISTING"
>EXEC SQL INCLUDE sqlda.h;
sqlda_t *sqlda; /* This doesn't need to be under embedded DECLARE SECTION */
EXEC SQL BEGIN DECLARE SECTION;
char *prep_stmt = "select * from table1";
int i;
EXEC SQL END DECLARE SECTION;
...
EXEC SQL PREPARE mystmt FROM :prep_stmt;
EXEC SQL DESCRIBE mystmt INTO sqlda;
printf("# of fields: %d\n", sqlda->sqld);
for (i = 0; i < sqlda->sqld; i++)
printf("field %d: \"%s\"\n", sqlda->sqlvar[i]->sqlname);
EXEC SQL DECLARE mycursor CURSOR FOR mystmt;
EXEC SQL OPEN mycursor;
EXEC SQL WHENEVER NOT FOUND GOTO out;
while (1)
{
EXEC SQL FETCH mycursor USING sqlda;
}
EXEC SQL CLOSE mycursor;
free(sqlda); /* The main structure is all to be free(),
* sqlda and sqlda->sqlvar is in one allocated area */</PRE
><P>
For more information, see the <TT
CLASS="LITERAL"
>sqlda.h</TT
> header and the
<TT
CLASS="LITERAL"
>src/interfaces/ecpg/test/compat_informix/sqlda.pgc</TT
> regression test.
</P
></DIV
><DIV
CLASS="SECT2"
><H2
CLASS="SECT2"
><A
NAME="ECPG-INFORMIX-FUNCTIONS"
>33.15.4. Additional Functions</A
></H2
><P
> <P
></P
></P><DIV
CLASS="VARIABLELIST"
><DL
><DT
><CODE
CLASS="FUNCTION"
>decadd</CODE
></DT
><DD
><P
> Add two decimal type values.
</P><PRE
CLASS="SYNOPSIS"
>int decadd(decimal *arg1, decimal *arg2, decimal *sum);</PRE
><P>
The function receives a pointer to the first operand of type decimal
(<TT
CLASS="LITERAL"
>arg1</TT
>), a pointer to the second operand of type decimal
(<TT
CLASS="LITERAL"
>arg2</TT
>) and a pointer to a value of type decimal that will
contain the sum (<TT
CLASS="LITERAL"
>sum</TT
>). On success, the function returns 0.
<TT
CLASS="SYMBOL"
>ECPG_INFORMIX_NUM_OVERFLOW</TT
> is returned in case of overflow and
<TT
CLASS="SYMBOL"
>ECPG_INFORMIX_NUM_UNDERFLOW</TT
> in case of underflow. -1 is returned for
other failures and <TT
CLASS="VARNAME"
>errno</TT
> is set to the respective <TT
CLASS="VARNAME"
>errno</TT
> number of the
pgtypeslib.
</P
></DD
><DT
><CODE
CLASS="FUNCTION"
>deccmp</CODE
></DT
><DD
><P
> Compare two variables of type decimal.
</P><PRE
CLASS="SYNOPSIS"
>int deccmp(decimal *arg1, decimal *arg2);</PRE
><P>
The function receives a pointer to the first decimal value
(<TT
CLASS="LITERAL"
>arg1</TT
>), a pointer to the second decimal value
(<TT
CLASS="LITERAL"
>arg2</TT
>) and returns an integer value that indicates which is
the bigger value.
<P
></P
></P><UL
><LI
><P
> 1, if the value that <TT
CLASS="LITERAL"
>arg1</TT
> points to is bigger than the
value that <TT
CLASS="LITERAL"
>var2</TT
> points to
</P
></LI
><LI
><P
> -1, if the value that <TT
CLASS="LITERAL"
>arg1</TT
> points to is smaller than the
value that <TT
CLASS="LITERAL"
>arg2</TT
> points to </P
></LI
><LI
><P
> 0, if the value that <TT
CLASS="LITERAL"
>arg1</TT
> points to and the value that
<TT
CLASS="LITERAL"
>arg2</TT
> points to are equal
</P
></LI
></UL
><P>
</P
></DD
><DT
><CODE
CLASS="FUNCTION"
>deccopy</CODE
></DT
><DD
><P
> Copy a decimal value.
</P><PRE
CLASS="SYNOPSIS"
>void deccopy(decimal *src, decimal *target);</PRE
><P>
The function receives a pointer to the decimal value that should be
copied as the first argument (<TT
CLASS="LITERAL"
>src</TT
>) and a pointer to the
target structure of type decimal (<TT
CLASS="LITERAL"
>target</TT
>) as the second
argument.
</P
></DD
><DT
><CODE
CLASS="FUNCTION"
>deccvasc</CODE
></DT
><DD
><P
> Convert a value from its ASCII representation into a decimal type.
</P><PRE
CLASS="SYNOPSIS"
>int deccvasc(char *cp, int len, decimal *np);</PRE
><P>
The function receives a pointer to string that contains the string
representation of the number to be converted (<TT
CLASS="LITERAL"
>cp</TT
>) as well
as its length <TT
CLASS="LITERAL"
>len</TT
>. <TT
CLASS="LITERAL"
>np</TT
> is a pointer to the
decimal value that saves the result of the operation.
</P
><P
> Valid formats are for example:
<TT
CLASS="LITERAL"
>-2</TT
>,
<TT
CLASS="LITERAL"
>.794</TT
>,
<TT
CLASS="LITERAL"
>+3.44</TT
>,
<TT
CLASS="LITERAL"
>592.49E07</TT
> or
<TT
CLASS="LITERAL"
>-32.84e-4</TT
>.
</P
><P
> The function returns 0 on success. If overflow or underflow occurred,
<TT
CLASS="LITERAL"
>ECPG_INFORMIX_NUM_OVERFLOW</TT
> or
<TT
CLASS="LITERAL"
>ECPG_INFORMIX_NUM_UNDERFLOW</TT
> is returned. If the ASCII
representation could not be parsed,
<TT
CLASS="LITERAL"
>ECPG_INFORMIX_BAD_NUMERIC</TT
> is returned or
<TT
CLASS="LITERAL"
>ECPG_INFORMIX_BAD_EXPONENT</TT
> if this problem occurred while
parsing the exponent.
</P
></DD
><DT
><CODE
CLASS="FUNCTION"
>deccvdbl</CODE
></DT
><DD
><P
> Convert a value of type double to a value of type decimal.
</P><PRE
CLASS="SYNOPSIS"
>int deccvdbl(double dbl, decimal *np);</PRE
><P>
The function receives the variable of type double that should be
converted as its first argument (<TT
CLASS="LITERAL"
>dbl</TT
>). As the second
argument (<TT
CLASS="LITERAL"
>np</TT
>), the function receives a pointer to the
decimal variable that should hold the result of the operation.
</P
><P
> The function returns 0 on success and a negative value if the
conversion failed.
</P
></DD
><DT
><CODE
CLASS="FUNCTION"
>deccvint</CODE
></DT
><DD
><P
> Convert a value of type int to a value of type decimal.
</P><PRE
CLASS="SYNOPSIS"
>int deccvint(int in, decimal *np);</PRE
><P>
The function receives the variable of type int that should be
converted as its first argument (<TT
CLASS="LITERAL"
>in</TT
>). As the second
argument (<TT
CLASS="LITERAL"
>np</TT
>), the function receives a pointer to the
decimal variable that should hold the result of the operation.
</P
><P
> The function returns 0 on success and a negative value if the
conversion failed.
</P
></DD
><DT
><CODE
CLASS="FUNCTION"
>deccvlong</CODE
></DT
><DD
><P
> Convert a value of type long to a value of type decimal.
</P><PRE
CLASS="SYNOPSIS"
>int deccvlong(long lng, decimal *np);</PRE
><P>
The function receives the variable of type long that should be
converted as its first argument (<TT
CLASS="LITERAL"
>lng</TT
>). As the second
argument (<TT
CLASS="LITERAL"
>np</TT
>), the function receives a pointer to the
decimal variable that should hold the result of the operation.
</P
><P
> The function returns 0 on success and a negative value if the
conversion failed.
</P
></DD
><DT
><CODE
CLASS="FUNCTION"
>decdiv</CODE
></DT
><DD
><P
> Divide two variables of type decimal.
</P><PRE
CLASS="SYNOPSIS"
>int decdiv(decimal *n1, decimal *n2, decimal *result);</PRE
><P>
The function receives pointers to the variables that are the first
(<TT
CLASS="LITERAL"
>n1</TT
>) and the second (<TT
CLASS="LITERAL"
>n2</TT
>) operands and
calculates <TT
CLASS="LITERAL"
>n1</TT
>/<TT
CLASS="LITERAL"
>n2</TT
>. <TT
CLASS="LITERAL"
>result</TT
> is a
pointer to the variable that should hold the result of the operation.
</P
><P
> On success, 0 is returned and a negative value if the division fails.
If overflow or underflow occurred, the function returns
<TT
CLASS="LITERAL"
>ECPG_INFORMIX_NUM_OVERFLOW</TT
> or
<TT
CLASS="LITERAL"
>ECPG_INFORMIX_NUM_UNDERFLOW</TT
> respectively. If an attempt to
divide by zero is observed, the function returns
<TT
CLASS="LITERAL"
>ECPG_INFORMIX_DIVIDE_ZERO</TT
>.
</P
></DD
><DT
><CODE
CLASS="FUNCTION"
>decmul</CODE
></DT
><DD
><P
> Multiply two decimal values.
</P><PRE
CLASS="SYNOPSIS"
>int decmul(decimal *n1, decimal *n2, decimal *result);</PRE
><P>
The function receives pointers to the variables that are the first
(<TT
CLASS="LITERAL"
>n1</TT
>) and the second (<TT
CLASS="LITERAL"
>n2</TT
>) operands and
calculates <TT
CLASS="LITERAL"
>n1</TT
>*<TT
CLASS="LITERAL"
>n2</TT
>. <TT
CLASS="LITERAL"
>result</TT
> is a
pointer to the variable that should hold the result of the operation.
</P
><P
> On success, 0 is returned and a negative value if the multiplication
fails. If overflow or underflow occurred, the function returns
<TT
CLASS="LITERAL"
>ECPG_INFORMIX_NUM_OVERFLOW</TT
> or
<TT
CLASS="LITERAL"
>ECPG_INFORMIX_NUM_UNDERFLOW</TT
> respectively.
</P
></DD
><DT
><CODE
CLASS="FUNCTION"
>decsub</CODE
></DT
><DD
><P
> Subtract one decimal value from another.
</P><PRE
CLASS="SYNOPSIS"
>int decsub(decimal *n1, decimal *n2, decimal *result);</PRE
><P>
The function receives pointers to the variables that are the first
(<TT
CLASS="LITERAL"
>n1</TT
>) and the second (<TT
CLASS="LITERAL"
>n2</TT
>) operands and
calculates <TT
CLASS="LITERAL"
>n1</TT
>-<TT
CLASS="LITERAL"
>n2</TT
>. <TT
CLASS="LITERAL"
>result</TT
> is a
pointer to the variable that should hold the result of the operation.
</P
><P
> On success, 0 is returned and a negative value if the subtraction
fails. If overflow or underflow occurred, the function returns
<TT
CLASS="LITERAL"
>ECPG_INFORMIX_NUM_OVERFLOW</TT
> or
<TT
CLASS="LITERAL"
>ECPG_INFORMIX_NUM_UNDERFLOW</TT
> respectively.
</P
></DD
><DT
><CODE
CLASS="FUNCTION"
>dectoasc</CODE
></DT
><DD
><P
> Convert a variable of type decimal to its ASCII representation in a C
char* string.
</P><PRE
CLASS="SYNOPSIS"
>int dectoasc(decimal *np, char *cp, int len, int right)</PRE
><P>
The function receives a pointer to a variable of type decimal
(<TT
CLASS="LITERAL"
>np</TT
>) that it converts to its textual representation.
<TT
CLASS="LITERAL"
>cp</TT
> is the buffer that should hold the result of the
operation. The parameter <TT
CLASS="LITERAL"
>right</TT
> specifies, how many digits
right of the decimal point should be included in the output. The result
will be rounded to this number of decimal digits. Setting
<TT
CLASS="LITERAL"
>right</TT
> to -1 indicates that all available decimal digits
should be included in the output. If the length of the output buffer,
which is indicated by <TT
CLASS="LITERAL"
>len</TT
> is not sufficient to hold the
textual representation including the trailing zero byte, only a
single <TT
CLASS="LITERAL"
>*</TT
> character is stored in the result and -1 is
returned.
</P
><P
> The function returns either -1 if the buffer <TT
CLASS="LITERAL"
>cp</TT
> was too
small or <TT
CLASS="LITERAL"
>ECPG_INFORMIX_OUT_OF_MEMORY</TT
> if memory was
exhausted.
</P
></DD
><DT
><CODE
CLASS="FUNCTION"
>dectodbl</CODE
></DT
><DD
><P
> Convert a variable of type decimal to a double.
</P><PRE
CLASS="SYNOPSIS"
>int dectodbl(decimal *np, double *dblp);</PRE
><P>
The function receives a pointer to the decimal value to convert
(<TT
CLASS="LITERAL"
>np</TT
>) and a pointer to the double variable that
should hold the result of the operation (<TT
CLASS="LITERAL"
>dblp</TT
>).
</P
><P
> On success, 0 is returned and a negative value if the conversion
failed.
</P
></DD
><DT
><CODE
CLASS="FUNCTION"
>dectoint</CODE
></DT
><DD
><P
> Convert a variable to type decimal to an integer.
</P><PRE
CLASS="SYNOPSIS"
>int dectoint(decimal *np, int *ip);</PRE
><P>
The function receives a pointer to the decimal value to convert
(<TT
CLASS="LITERAL"
>np</TT
>) and a pointer to the integer variable that
should hold the result of the operation (<TT
CLASS="LITERAL"
>ip</TT
>).
</P
><P
> On success, 0 is returned and a negative value if the conversion
failed. If an overflow occurred, <TT
CLASS="LITERAL"
>ECPG_INFORMIX_NUM_OVERFLOW</TT
>
is returned.
</P
><P
> Note that the ECPG implementation differs from the <SPAN
CLASS="PRODUCTNAME"
>Informix</SPAN
>
implementation. <SPAN
CLASS="PRODUCTNAME"
>Informix</SPAN
> limits an integer to the range from -32767 to
32767, while the limits in the ECPG implementation depend on the
architecture (<TT
CLASS="LITERAL"
>-INT_MAX .. INT_MAX</TT
>).
</P
></DD
><DT
><CODE
CLASS="FUNCTION"
>dectolong</CODE
></DT
><DD
><P
> Convert a variable to type decimal to a long integer.
</P><PRE
CLASS="SYNOPSIS"
>int dectolong(decimal *np, long *lngp);</PRE
><P>
The function receives a pointer to the decimal value to convert
(<TT
CLASS="LITERAL"
>np</TT
>) and a pointer to the long variable that
should hold the result of the operation (<TT
CLASS="LITERAL"
>lngp</TT
>).
</P
><P
> On success, 0 is returned and a negative value if the conversion
failed. If an overflow occurred, <TT
CLASS="LITERAL"
>ECPG_INFORMIX_NUM_OVERFLOW</TT
>
is returned.
</P
><P
> Note that the ECPG implementation differs from the <SPAN
CLASS="PRODUCTNAME"
>Informix</SPAN
>
implementation. <SPAN
CLASS="PRODUCTNAME"
>Informix</SPAN
> limits a long integer to the range from
-2,147,483,647 to 2,147,483,647, while the limits in the ECPG
implementation depend on the architecture (<TT
CLASS="LITERAL"
>-LONG_MAX ..
LONG_MAX</TT
>).
</P
></DD
><DT
><CODE
CLASS="FUNCTION"
>rdatestr</CODE
></DT
><DD
><P
> Converts a date to a C char* string.
</P><PRE
CLASS="SYNOPSIS"
>int rdatestr(date d, char *str);</PRE
><P>
The function receives two arguments, the first one is the date to
convert (<TT
CLASS="LITERAL"
>d</TT
>) and the second one is a pointer to the target
string. The output format is always <TT
CLASS="LITERAL"
>yyyy-mm-dd</TT
>, so you need
to allocate at least 11 bytes (including the zero-byte terminator) for the
string.
</P
><P
> The function returns 0 on success and a negative value in case of
error.
</P
><P
> Note that ECPG's implementation differs from the <SPAN
CLASS="PRODUCTNAME"
>Informix</SPAN
>
implementation. In <SPAN
CLASS="PRODUCTNAME"
>Informix</SPAN
> the format can be influenced by setting
environment variables. In ECPG however, you cannot change the output
format.
</P
></DD
><DT
><CODE
CLASS="FUNCTION"
>rstrdate</CODE
></DT
><DD
><P
> Parse the textual representation of a date.
</P><PRE
CLASS="SYNOPSIS"
>int rstrdate(char *str, date *d);</PRE
><P>
The function receives the textual representation of the date to convert
(<TT
CLASS="LITERAL"
>str</TT
>) and a pointer to a variable of type date
(<TT
CLASS="LITERAL"
>d</TT
>). This function does not allow you to specify a format
mask. It uses the default format mask of <SPAN
CLASS="PRODUCTNAME"
>Informix</SPAN
> which is
<TT
CLASS="LITERAL"
>mm/dd/yyyy</TT
>. Internally, this function is implemented by
means of <CODE
CLASS="FUNCTION"
>rdefmtdate</CODE
>. Therefore, <CODE
CLASS="FUNCTION"
>rstrdate</CODE
> is
not faster and if you have the choice you should opt for
<CODE
CLASS="FUNCTION"
>rdefmtdate</CODE
> which allows you to specify the format mask
explicitly.
</P
><P
> The function returns the same values as <CODE
CLASS="FUNCTION"
>rdefmtdate</CODE
>.
</P
></DD
><DT
><CODE
CLASS="FUNCTION"
>rtoday</CODE
></DT
><DD
><P
> Get the current date.
</P><PRE
CLASS="SYNOPSIS"
>void rtoday(date *d);</PRE
><P>
The function receives a pointer to a date variable (<TT
CLASS="LITERAL"
>d</TT
>)
that it sets to the current date.
</P
><P
> Internally this function uses the <A
HREF="ecpg-pgtypes.html#PGTYPESDATETODAY"
><I
CLASS="TERM"
><CODE
CLASS="FUNCTION"
>PGTYPESdate_today</CODE
></I
></A
>
function.
</P
></DD
><DT
><CODE
CLASS="FUNCTION"
>rjulmdy</CODE
></DT
><DD
><P
> Extract the values for the day, the month and the year from a variable
of type date.
</P><PRE
CLASS="SYNOPSIS"
>int rjulmdy(date d, short mdy[3]);</PRE
><P>
The function receives the date <TT
CLASS="LITERAL"
>d</TT
> and a pointer to an array
of 3 short integer values <TT
CLASS="LITERAL"
>mdy</TT
>. The variable name indicates
the sequential order: <TT
CLASS="LITERAL"
>mdy[0]</TT
> will be set to contain the
number of the month, <TT
CLASS="LITERAL"
>mdy[1]</TT
> will be set to the value of the
day and <TT
CLASS="LITERAL"
>mdy[2]</TT
> will contain the year.
</P
><P
> The function always returns 0 at the moment.
</P
><P
> Internally the function uses the <A
HREF="ecpg-pgtypes.html#PGTYPESDATEJULMDY"
><I
CLASS="TERM"
><CODE
CLASS="FUNCTION"
>PGTYPESdate_julmdy</CODE
></I
></A
>
function.
</P
></DD
><DT
><CODE
CLASS="FUNCTION"
>rdefmtdate</CODE
></DT
><DD
><P
> Use a format mask to convert a character string to a value of type
date.
</P><PRE
CLASS="SYNOPSIS"
>int rdefmtdate(date *d, char *fmt, char *str);</PRE
><P>
The function receives a pointer to the date value that should hold the
result of the operation (<TT
CLASS="LITERAL"
>d</TT
>), the format mask to use for
parsing the date (<TT
CLASS="LITERAL"
>fmt</TT
>) and the C char* string containing
the textual representation of the date (<TT
CLASS="LITERAL"
>str</TT
>). The textual
representation is expected to match the format mask. However you do not
need to have a 1:1 mapping of the string to the format mask. The
function only analyzes the sequential order and looks for the literals
<TT
CLASS="LITERAL"
>yy</TT
> or <TT
CLASS="LITERAL"
>yyyy</TT
> that indicate the
position of the year, <TT
CLASS="LITERAL"
>mm</TT
> to indicate the position of
the month and <TT
CLASS="LITERAL"
>dd</TT
> to indicate the position of the
day.
</P
><P
> The function returns the following values:
<P
></P
></P><UL
><LI
><P
> 0 - The function terminated successfully.
</P
></LI
><LI
><P
> <TT
CLASS="LITERAL"
>ECPG_INFORMIX_ENOSHORTDATE</TT
> - The date does not contain
delimiters between day, month and year. In this case the input
string must be exactly 6 or 8 bytes long but isn't.
</P
></LI
><LI
><P
> <TT
CLASS="LITERAL"
>ECPG_INFORMIX_ENOTDMY</TT
> - The format string did not
correctly indicate the sequential order of year, month and day.
</P
></LI
><LI
><P
> <TT
CLASS="LITERAL"
>ECPG_INFORMIX_BAD_DAY</TT
> - The input string does not
contain a valid day.
</P
></LI
><LI
><P
> <TT
CLASS="LITERAL"
>ECPG_INFORMIX_BAD_MONTH</TT
> - The input string does not
contain a valid month.
</P
></LI
><LI
><P
> <TT
CLASS="LITERAL"
>ECPG_INFORMIX_BAD_YEAR</TT
> - The input string does not
contain a valid year.
</P
></LI
></UL
><P>
</P
><P
> Internally this function is implemented to use the <A
HREF="ecpg-pgtypes.html#PGTYPESDATEDEFMTASC"
><I
CLASS="TERM"
><CODE
CLASS="FUNCTION"
>PGTYPESdate_defmt_asc</CODE
></I
></A
> function. See the reference there for a
table of example input.
</P
></DD
><DT
><CODE
CLASS="FUNCTION"
>rfmtdate</CODE
></DT
><DD
><P
> Convert a variable of type date to its textual representation using a
format mask.
</P><PRE
CLASS="SYNOPSIS"
>int rfmtdate(date d, char *fmt, char *str);</PRE
><P>
The function receives the date to convert (<TT
CLASS="LITERAL"
>d</TT
>), the format
mask (<TT
CLASS="LITERAL"
>fmt</TT
>) and the string that will hold the textual
representation of the date (<TT
CLASS="LITERAL"
>str</TT
>).
</P
><P
> On success, 0 is returned and a negative value if an error occurred.
</P
><P
> Internally this function uses the <A
HREF="ecpg-pgtypes.html#PGTYPESDATEFMTASC"
><I
CLASS="TERM"
><CODE
CLASS="FUNCTION"
>PGTYPESdate_fmt_asc</CODE
></I
></A
>
function, see the reference there for examples.
</P
></DD
><DT
><CODE
CLASS="FUNCTION"
>rmdyjul</CODE
></DT
><DD
><P
> Create a date value from an array of 3 short integers that specify the
day, the month and the year of the date.
</P><PRE
CLASS="SYNOPSIS"
>int rmdyjul(short mdy[3], date *d);</PRE
><P>
The function receives the array of the 3 short integers
(<TT
CLASS="LITERAL"
>mdy</TT
>) and a pointer to a variable of type date that should
hold the result of the operation.
</P
><P
> Currently the function returns always 0.
</P
><P
> Internally the function is implemented to use the function <A
HREF="ecpg-pgtypes.html#PGTYPESDATEMDYJUL"
><I
CLASS="TERM"
><CODE
CLASS="FUNCTION"
>PGTYPESdate_mdyjul</CODE
></I
></A
>.
</P
></DD
><DT
><CODE
CLASS="FUNCTION"
>rdayofweek</CODE
></DT
><DD
><P
> Return a number representing the day of the week for a date value.
</P><PRE
CLASS="SYNOPSIS"
>int rdayofweek(date d);</PRE
><P>
The function receives the date variable <TT
CLASS="LITERAL"
>d</TT
> as its only
argument and returns an integer that indicates the day of the week for
this date.
<P
></P
></P><UL
><LI
><P
> 0 - Sunday
</P
></LI
><LI
><P
> 1 - Monday
</P
></LI
><LI
><P
> 2 - Tuesday
</P
></LI
><LI
><P
> 3 - Wednesday
</P
></LI
><LI
><P
> 4 - Thursday
</P
></LI
><LI
><P
> 5 - Friday
</P
></LI
><LI
><P
> 6 - Saturday
</P
></LI
></UL
><P>
</P
><P
> Internally the function is implemented to use the function <A
HREF="ecpg-pgtypes.html#PGTYPESDATEDAYOFWEEK"
><I
CLASS="TERM"
><CODE
CLASS="FUNCTION"
>PGTYPESdate_dayofweek</CODE
></I
></A
>.
</P
></DD
><DT
><CODE
CLASS="FUNCTION"
>dtcurrent</CODE
></DT
><DD
><P
> Retrieve the current timestamp.
</P><PRE
CLASS="SYNOPSIS"
>void dtcurrent(timestamp *ts);</PRE
><P>
The function retrieves the current timestamp and saves it into the
timestamp variable that <TT
CLASS="LITERAL"
>ts</TT
> points to.
</P
></DD
><DT
><CODE
CLASS="FUNCTION"
>dtcvasc</CODE
></DT
><DD
><P
> Parses a timestamp from its textual representation
into a timestamp variable.
</P><PRE
CLASS="SYNOPSIS"
>int dtcvasc(char *str, timestamp *ts);</PRE
><P>
The function receives the string to parse (<TT
CLASS="LITERAL"
>str</TT
>) and a
pointer to the timestamp variable that should hold the result of the
operation (<TT
CLASS="LITERAL"
>ts</TT
>).
</P
><P
> The function returns 0 on success and a negative value in case of
error.
</P
><P
> Internally this function uses the <A
HREF="ecpg-pgtypes.html#PGTYPESTIMESTAMPFROMASC"
><I
CLASS="TERM"
><CODE
CLASS="FUNCTION"
>PGTYPEStimestamp_from_asc</CODE
></I
></A
> function. See the reference there
for a table with example inputs.
</P
></DD
><DT
><CODE
CLASS="FUNCTION"
>dtcvfmtasc</CODE
></DT
><DD
><P
> Parses a timestamp from its textual representation
using a format mask into a timestamp variable.
</P><PRE
CLASS="SYNOPSIS"
>dtcvfmtasc(char *inbuf, char *fmtstr, timestamp *dtvalue)</PRE
><P>
The function receives the string to parse (<TT
CLASS="LITERAL"
>inbuf</TT
>), the
format mask to use (<TT
CLASS="LITERAL"
>fmtstr</TT
>) and a pointer to the timestamp
variable that should hold the result of the operation
(<TT
CLASS="LITERAL"
>dtvalue</TT
>).
</P
><P
> This function is implemented by means of the <A
HREF="ecpg-pgtypes.html#PGTYPESTIMESTAMPDEFMTASC"
><I
CLASS="TERM"
><CODE
CLASS="FUNCTION"
>PGTYPEStimestamp_defmt_asc</CODE
></I
></A
> function. See the documentation
there for a list of format specifiers that can be used.
</P
><P
> The function returns 0 on success and a negative value in case of
error.
</P
></DD
><DT
><CODE
CLASS="FUNCTION"
>dtsub</CODE
></DT
><DD
><P
> Subtract one timestamp from another and return a variable of type
interval.
</P><PRE
CLASS="SYNOPSIS"
>int dtsub(timestamp *ts1, timestamp *ts2, interval *iv);</PRE
><P>
The function will subtract the timestamp variable that <TT
CLASS="LITERAL"
>ts2</TT
>
points to from the timestamp variable that <TT
CLASS="LITERAL"
>ts1</TT
> points to
and will store the result in the interval variable that <TT
CLASS="LITERAL"
>iv</TT
>
points to.
</P
><P
> Upon success, the function returns 0 and a negative value if an
error occurred.
</P
></DD
><DT
><CODE
CLASS="FUNCTION"
>dttoasc</CODE
></DT
><DD
><P
> Convert a timestamp variable to a C char* string.
</P><PRE
CLASS="SYNOPSIS"
>int dttoasc(timestamp *ts, char *output);</PRE
><P>
The function receives a pointer to the timestamp variable to convert
(<TT
CLASS="LITERAL"
>ts</TT
>) and the string that should hold the result of the
operation (<TT
CLASS="LITERAL"
>output</TT
>). It converts <TT
CLASS="LITERAL"
>ts</TT
> to its
textual representation according to the SQL standard, which is
be <TT
CLASS="LITERAL"
>YYYY-MM-DD HH:MM:SS</TT
>.
</P
><P
> Upon success, the function returns 0 and a negative value if an
error occurred.
</P
></DD
><DT
><CODE
CLASS="FUNCTION"
>dttofmtasc</CODE
></DT
><DD
><P
> Convert a timestamp variable to a C char* using a format mask.
</P><PRE
CLASS="SYNOPSIS"
>int dttofmtasc(timestamp *ts, char *output, int str_len, char *fmtstr);</PRE
><P>
The function receives a pointer to the timestamp to convert as its
first argument (<TT
CLASS="LITERAL"
>ts</TT
>), a pointer to the output buffer
(<TT
CLASS="LITERAL"
>output</TT
>), the maximal length that has been allocated for
the output buffer (<TT
CLASS="LITERAL"
>str_len</TT
>) and the format mask to
use for the conversion (<TT
CLASS="LITERAL"
>fmtstr</TT
>).
</P
><P
> Upon success, the function returns 0 and a negative value if an
error occurred.
</P
><P
> Internally, this function uses the <A
HREF="ecpg-pgtypes.html#PGTYPESTIMESTAMPFMTASC"
><I
CLASS="TERM"
><CODE
CLASS="FUNCTION"
>PGTYPEStimestamp_fmt_asc</CODE
></I
></A
> function. See the reference there for
information on what format mask specifiers can be used.
</P
></DD
><DT
><CODE
CLASS="FUNCTION"
>intoasc</CODE
></DT
><DD
><P
> Convert an interval variable to a C char* string.
</P><PRE
CLASS="SYNOPSIS"
>int intoasc(interval *i, char *str);</PRE
><P>
The function receives a pointer to the interval variable to convert
(<TT
CLASS="LITERAL"
>i</TT
>) and the string that should hold the result of the
operation (<TT
CLASS="LITERAL"
>str</TT
>). It converts <TT
CLASS="LITERAL"
>i</TT
> to its
textual representation according to the SQL standard, which is
be <TT
CLASS="LITERAL"
>YYYY-MM-DD HH:MM:SS</TT
>.
</P
><P
> Upon success, the function returns 0 and a negative value if an
error occurred.
</P
></DD
><DT
><CODE
CLASS="FUNCTION"
>rfmtlong</CODE
></DT
><DD
><P
> Convert a long integer value to its textual representation using a
format mask.
</P><PRE
CLASS="SYNOPSIS"
>int rfmtlong(long lng_val, char *fmt, char *outbuf);</PRE
><P>
The function receives the long value <TT
CLASS="LITERAL"
>lng_val</TT
>, the format
mask <TT
CLASS="LITERAL"
>fmt</TT
> and a pointer to the output buffer
<TT
CLASS="LITERAL"
>outbuf</TT
>. It converts the long value according to the format
mask to its textual representation.
</P
><P
> The format mask can be composed of the following format specifying
characters:
<P
></P
></P><UL
><LI
><P
> <TT
CLASS="LITERAL"
>*</TT
> (asterisk) - if this position would be blank
otherwise, fill it with an asterisk.
</P
></LI
><LI
><P
> <TT
CLASS="LITERAL"
>&</TT
> (ampersand) - if this position would be
blank otherwise, fill it with a zero.
</P
></LI
><LI
><P
> <TT
CLASS="LITERAL"
>#</TT
> - turn leading zeroes into blanks.
</P
></LI
><LI
><P
> <TT
CLASS="LITERAL"
><</TT
> - left-justify the number in the string.
</P
></LI
><LI
><P
> <TT
CLASS="LITERAL"
>,</TT
> (comma) - group numbers of four or more digits
into groups of three digits separated by a comma.
</P
></LI
><LI
><P
> <TT
CLASS="LITERAL"
>.</TT
> (period) - this character separates the
whole-number part of the number from the fractional part.
</P
></LI
><LI
><P
> <TT
CLASS="LITERAL"
>-</TT
> (minus) - the minus sign appears if the number
is a negative value.
</P
></LI
><LI
><P
> <TT
CLASS="LITERAL"
>+</TT
> (plus) - the plus sign appears if the number is
a positive value.
</P
></LI
><LI
><P
> <TT
CLASS="LITERAL"
>(</TT
> - this replaces the minus sign in front of the
negative number. The minus sign will not appear.
</P
></LI
><LI
><P
> <TT
CLASS="LITERAL"
>)</TT
> - this character replaces the minus and is
printed behind the negative value.
</P
></LI
><LI
><P
> <TT
CLASS="LITERAL"
>$</TT
> - the currency symbol.
</P
></LI
></UL
><P>
</P
></DD
><DT
><CODE
CLASS="FUNCTION"
>rupshift</CODE
></DT
><DD
><P
> Convert a string to upper case.
</P><PRE
CLASS="SYNOPSIS"
>void rupshift(char *str);</PRE
><P>
The function receives a pointer to the string and transforms every
lower case character to upper case.
</P
></DD
><DT
><CODE
CLASS="FUNCTION"
>byleng</CODE
></DT
><DD
><P
> Return the number of characters in a string without counting trailing
blanks.
</P><PRE
CLASS="SYNOPSIS"
>int byleng(char *str, int len);</PRE
><P>
The function expects a fixed-length string as its first argument
(<TT
CLASS="LITERAL"
>str</TT
>) and its length as its second argument
(<TT
CLASS="LITERAL"
>len</TT
>). It returns the number of significant characters,
that is the length of the string without trailing blanks.
</P
></DD
><DT
><CODE
CLASS="FUNCTION"
>ldchar</CODE
></DT
><DD
><P
> Copy a fixed-length string into a null-terminated string.
</P><PRE
CLASS="SYNOPSIS"
>void ldchar(char *src, int len, char *dest);</PRE
><P>
The function receives the fixed-length string to copy
(<TT
CLASS="LITERAL"
>src</TT
>), its length (<TT
CLASS="LITERAL"
>len</TT
>) and a pointer to the
destination memory (<TT
CLASS="LITERAL"
>dest</TT
>). Note that you need to reserve at
least <TT
CLASS="LITERAL"
>len+1</TT
> bytes for the string that <TT
CLASS="LITERAL"
>dest</TT
>
points to. The function copies at most <TT
CLASS="LITERAL"
>len</TT
> bytes to the new
location (less if the source string has trailing blanks) and adds the
null-terminator.
</P
></DD
><DT
><CODE
CLASS="FUNCTION"
>rgetmsg</CODE
></DT
><DD
><P
></P><PRE
CLASS="SYNOPSIS"
>int rgetmsg(int msgnum, char *s, int maxsize);</PRE
><P>
This function exists but is not implemented at the moment!
</P
></DD
><DT
><CODE
CLASS="FUNCTION"
>rtypalign</CODE
></DT
><DD
><P
></P><PRE
CLASS="SYNOPSIS"
>int rtypalign(int offset, int type);</PRE
><P>
This function exists but is not implemented at the moment!
</P
></DD
><DT
><CODE
CLASS="FUNCTION"
>rtypmsize</CODE
></DT
><DD
><P
></P><PRE
CLASS="SYNOPSIS"
>int rtypmsize(int type, int len);</PRE
><P>
This function exists but is not implemented at the moment!
</P
></DD
><DT
><CODE
CLASS="FUNCTION"
>rtypwidth</CODE
></DT
><DD
><P
></P><PRE
CLASS="SYNOPSIS"
>int rtypwidth(int sqltype, int sqllen);</PRE
><P>
This function exists but is not implemented at the moment!
</P
></DD
><DT
><A
NAME="RSETNULL"
></A
><CODE
CLASS="FUNCTION"
>rsetnull</CODE
></DT
><DD
><P
> Set a variable to NULL.
</P><PRE
CLASS="SYNOPSIS"
>int rsetnull(int t, char *ptr);</PRE
><P>
The function receives an integer that indicates the type of the
variable and a pointer to the variable itself that is cast to a C
char* pointer.
</P
><P
> The following types exist:
<P
></P
></P><UL
><LI
><P
> <TT
CLASS="LITERAL"
>CCHARTYPE</TT
> - For a variable of type <TT
CLASS="TYPE"
>char</TT
> or <TT
CLASS="TYPE"
>char*</TT
>
</P
></LI
><LI
><P
> <TT
CLASS="LITERAL"
>CSHORTTYPE</TT
> - For a variable of type <TT
CLASS="TYPE"
>short int</TT
>
</P
></LI
><LI
><P
> <TT
CLASS="LITERAL"
>CINTTYPE</TT
> - For a variable of type <TT
CLASS="TYPE"
>int</TT
>
</P
></LI
><LI
><P
> <TT
CLASS="LITERAL"
>CBOOLTYPE</TT
> - For a variable of type <TT
CLASS="TYPE"
>boolean</TT
>
</P
></LI
><LI
><P
> <TT
CLASS="LITERAL"
>CFLOATTYPE</TT
> - For a variable of type <TT
CLASS="TYPE"
>float</TT
>
</P
></LI
><LI
><P
> <TT
CLASS="LITERAL"
>CLONGTYPE</TT
> - For a variable of type <TT
CLASS="TYPE"
>long</TT
>
</P
></LI
><LI
><P
> <TT
CLASS="LITERAL"
>CDOUBLETYPE</TT
> - For a variable of type <TT
CLASS="TYPE"
>double</TT
>
</P
></LI
><LI
><P
> <TT
CLASS="LITERAL"
>CDECIMALTYPE</TT
> - For a variable of type <TT
CLASS="TYPE"
>decimal</TT
>
</P
></LI
><LI
><P
> <TT
CLASS="LITERAL"
>CDATETYPE</TT
> - For a variable of type <TT
CLASS="TYPE"
>date</TT
>
</P
></LI
><LI
><P
> <TT
CLASS="LITERAL"
>CDTIMETYPE</TT
> - For a variable of type <TT
CLASS="TYPE"
>timestamp</TT
>
</P
></LI
></UL
><P>
</P
><P
> Here is an example of a call to this function:
</P><PRE
CLASS="PROGRAMLISTING"
>$char c[] = "abc ";
$short s = 17;
$int i = -74874;
rsetnull(CCHARTYPE, (char *) c);
rsetnull(CSHORTTYPE, (char *) &s);
rsetnull(CINTTYPE, (char *) &i);</PRE
><P>
</P
></DD
><DT
><CODE
CLASS="FUNCTION"
>risnull</CODE
></DT
><DD
><P
> Test if a variable is NULL.
</P><PRE
CLASS="SYNOPSIS"
>int risnull(int t, char *ptr);</PRE
><P>
The function receives the type of the variable to test (<TT
CLASS="LITERAL"
>t</TT
>)
as well a pointer to this variable (<TT
CLASS="LITERAL"
>ptr</TT
>). Note that the
latter needs to be cast to a char*. See the function <A
HREF="ecpg-informix-compat.html#RSETNULL"
><I
CLASS="TERM"
><CODE
CLASS="FUNCTION"
>rsetnull</CODE
></I
></A
> for a list of possible variable types.
</P
><P
> Here is an example of how to use this function:
</P><PRE
CLASS="PROGRAMLISTING"
>$char c[] = "abc ";
$short s = 17;
$int i = -74874;
risnull(CCHARTYPE, (char *) c);
risnull(CSHORTTYPE, (char *) &s);
risnull(CINTTYPE, (char *) &i);</PRE
><P>
</P
></DD
></DL
></DIV
><P>
</P
></DIV
><DIV
CLASS="SECT2"
><H2
CLASS="SECT2"
><A
NAME="ECPG-INFORMIX-CONSTANTS"
>33.15.5. Additional Constants</A
></H2
><P
> Note that all constants here describe errors and all of them are defined
to represent negative values. In the descriptions of the different
constants you can also find the value that the constants represent in the
current implementation. However you should not rely on this number. You can
however rely on the fact all of them are defined to represent negative
values.
<P
></P
></P><DIV
CLASS="VARIABLELIST"
><DL
><DT
><TT
CLASS="LITERAL"
>ECPG_INFORMIX_NUM_OVERFLOW</TT
></DT
><DD
><P
> Functions return this value if an overflow occurred in a
calculation. Internally it is defined as -1200 (the <SPAN
CLASS="PRODUCTNAME"
>Informix</SPAN
>
definition).
</P
></DD
><DT
><TT
CLASS="LITERAL"
>ECPG_INFORMIX_NUM_UNDERFLOW</TT
></DT
><DD
><P
> Functions return this value if an underflow occurred in a calculation.
Internally it is defined as -1201 (the <SPAN
CLASS="PRODUCTNAME"
>Informix</SPAN
> definition).
</P
></DD
><DT
><TT
CLASS="LITERAL"
>ECPG_INFORMIX_DIVIDE_ZERO</TT
></DT
><DD
><P
> Functions return this value if an attempt to divide by zero is
observed. Internally it is defined as -1202 (the <SPAN
CLASS="PRODUCTNAME"
>Informix</SPAN
> definition).
</P
></DD
><DT
><TT
CLASS="LITERAL"
>ECPG_INFORMIX_BAD_YEAR</TT
></DT
><DD
><P
> Functions return this value if a bad value for a year was found while
parsing a date. Internally it is defined as -1204 (the <SPAN
CLASS="PRODUCTNAME"
>Informix</SPAN
>
definition).
</P
></DD
><DT
><TT
CLASS="LITERAL"
>ECPG_INFORMIX_BAD_MONTH</TT
></DT
><DD
><P
> Functions return this value if a bad value for a month was found while
parsing a date. Internally it is defined as -1205 (the <SPAN
CLASS="PRODUCTNAME"
>Informix</SPAN
>
definition).
</P
></DD
><DT
><TT
CLASS="LITERAL"
>ECPG_INFORMIX_BAD_DAY</TT
></DT
><DD
><P
> Functions return this value if a bad value for a day was found while
parsing a date. Internally it is defined as -1206 (the <SPAN
CLASS="PRODUCTNAME"
>Informix</SPAN
>
definition).
</P
></DD
><DT
><TT
CLASS="LITERAL"
>ECPG_INFORMIX_ENOSHORTDATE</TT
></DT
><DD
><P
> Functions return this value if a parsing routine needs a short date
representation but did not get the date string in the right length.
Internally it is defined as -1209 (the <SPAN
CLASS="PRODUCTNAME"
>Informix</SPAN
> definition).
</P
></DD
><DT
><TT
CLASS="LITERAL"
>ECPG_INFORMIX_DATE_CONVERT</TT
></DT
><DD
><P
> Functions return this value if an error occurred during date
formatting. Internally it is defined as -1210 (the
<SPAN
CLASS="PRODUCTNAME"
>Informix</SPAN
> definition).
</P
></DD
><DT
><TT
CLASS="LITERAL"
>ECPG_INFORMIX_OUT_OF_MEMORY</TT
></DT
><DD
><P
> Functions return this value if memory was exhausted during
their operation. Internally it is defined as -1211 (the
<SPAN
CLASS="PRODUCTNAME"
>Informix</SPAN
> definition).
</P
></DD
><DT
><TT
CLASS="LITERAL"
>ECPG_INFORMIX_ENOTDMY</TT
></DT
><DD
><P
> Functions return this value if a parsing routine was supposed to get a
format mask (like <TT
CLASS="LITERAL"
>mmddyy</TT
>) but not all fields were listed
correctly. Internally it is defined as -1212 (the <SPAN
CLASS="PRODUCTNAME"
>Informix</SPAN
> definition).
</P
></DD
><DT
><TT
CLASS="LITERAL"
>ECPG_INFORMIX_BAD_NUMERIC</TT
></DT
><DD
><P
> Functions return this value either if a parsing routine cannot parse
the textual representation for a numeric value because it contains
errors or if a routine cannot complete a calculation involving numeric
variables because at least one of the numeric variables is invalid.
Internally it is defined as -1213 (the <SPAN
CLASS="PRODUCTNAME"
>Informix</SPAN
> definition).
</P
></DD
><DT
><TT
CLASS="LITERAL"
>ECPG_INFORMIX_BAD_EXPONENT</TT
></DT
><DD
><P
> Functions return this value if a parsing routine cannot parse
an exponent. Internally it is defined as -1216 (the
<SPAN
CLASS="PRODUCTNAME"
>Informix</SPAN
> definition).
</P
></DD
><DT
><TT
CLASS="LITERAL"
>ECPG_INFORMIX_BAD_DATE</TT
></DT
><DD
><P
> Functions return this value if a parsing routine cannot parse
a date. Internally it is defined as -1218 (the
<SPAN
CLASS="PRODUCTNAME"
>Informix</SPAN
> definition).
</P
></DD
><DT
><TT
CLASS="LITERAL"
>ECPG_INFORMIX_EXTRA_CHARS</TT
></DT
><DD
><P
> Functions return this value if a parsing routine is passed extra
characters it cannot parse. Internally it is defined as -1264 (the
<SPAN
CLASS="PRODUCTNAME"
>Informix</SPAN
> definition).
</P
></DD
></DL
></DIV
><P>
</P
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