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(mysql.info)mysql_real_escape_string

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`mysql_real_escape_string()'
............................

`unsigned int mysql_real_escape_string(MYSQL *mysql, char *to, const
char *from, unsigned int length)'

Description
...........

This function is used to create a legal SQL string that you can use in a
SQL statement. Note: String syntax.

The string in `from' is encoded to an escaped SQL string, taking into
account the current character set of the connection. The result is
placed in `to' and a terminating null byte is appended.  Characters
encoded are `NUL' (ASCII 0), `\n', `\r', `\', `'', `"', and Control-Z
(Note: Literals).

The string pointed to by `from' must be `length' bytes long.  You must
allocate the `to' buffer to be at least `length*2+1' bytes long.  (In
the worse case, each character may need to be encoded as using two
bytes, and you need room for the terminating null byte.)  When
`mysql_escape_string()' returns, the contents of `to' will be a
null-terminated string.  The return value is the length of the encoded
string, not including the terminating null character.

Example
.......

     char query[1000],*end;
     
     end = strmov(query,"INSERT INTO test_table values(");
     *end++ = '\'';
     end += mysql_real_escape_string(&mysql, end,"What's this",11);
     *end++ = '\'';
     *end++ = ',';
     *end++ = '\'';
     end += mysql_real_escape_string(&mysql, end,"binary data: \0\r\n",16);
     *end++ = '\'';
     *end++ = ')';
     
     if (mysql_real_query(&mysql,query,(unsigned int) (end - query)))
     {
        fprintf(stderr, "Failed to insert row, Error: %s\n",
                mysql_error(&mysql));
     }

The `strmov()' function used in the example is included in the
`mysqlclient' library and works like `strcpy()' but returns a pointer
to the terminating null of the first parameter.

Return Values
.............

The length of the value placed into `to', not including the terminating
null character.

Errors
......

None.