Difference between revisions of "Dbkeytoa()"
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<input parameters> | <input parameters> | ||
| − | char *key; | + | char *key; /* Key to be converted */ |
| − | char ascii[0]; /* Number of decimal places for numeric key */ | + | char ascii[0]; /* Number of decimal places for numeric key */ |
| − | char ascii[1]; /* Key type: 'D' – for DATE, 'N' – for NUMERIC */ | + | char ascii[1]; /* Key type: 'D' – for DATE, 'N' – for NUMERIC */ |
<output parameters> | <output parameters> | ||
| − | char *ascii; | + | char *ascii; /* Address of an ASCII string representing the converted key value */ |
</code> | </code> | ||
| Line 36: | Line 36: | ||
The first example converts an .NDX file numeric key stored in "char key[8]" to an ASCII string which is placed in "char ascii[64]". The converted ASCII string has a precision of 3 decimal places. The converted key is printed on standard output. | The first example converts an .NDX file numeric key stored in "char key[8]" to an ASCII string which is placed in "char ascii[64]". The converted ASCII string has a precision of 3 decimal places. The converted key is printed on standard output. | ||
| + | |||
<code lang="c"> | <code lang="c"> | ||
#include "dbl.h" | #include "dbl.h" | ||
| − | char key[8]; | + | char key[8]; /* Key to be converted */ |
| − | char ascii[64]; /* Buffer for converted key | + | char ascii[64]; /* Buffer for converted key */ |
| − | int rc; /* Return code | + | int rc; /* Return code */ |
| − | ascii[0] = 3; | + | ascii[0] = 3; /* Specify number of decimal places */ |
| − | ascii[1] = 'N'; | + | ascii[1] = 'N'; /* Indicate the key is NUMERIC */ |
rc = dbkeytoa(key, ascii); | rc = dbkeytoa(key, ascii); | ||
| − | if (rc = = SUCCESS) printf("the key is '%s' n", ascii); | + | if (rc == SUCCESS) printf("the key is '%s' \n", ascii); |
else { | else { | ||
| − | printf("error number %d n", rc); | + | printf("error number %d \n", rc); |
exit (0); | exit (0); | ||
} | } | ||
</code> | </code> | ||
| + | |||
The second example reads the previous date key from the .NDX file specified by "char *ndx;", converts it from the .NDX date format to the ASCII date format and prints the key on the standard output. | The second example reads the previous date key from the .NDX file specified by "char *ndx;", converts it from the .NDX date format to the ASCII date format and prints the key on the standard output. | ||
| + | |||
<code lang="c"> | <code lang="c"> | ||
#include "dbl.h" | #include "dbl.h" | ||
| − | char *ndx; /* .NDX file descriptor | + | char *ndx; /* .NDX file descriptor */ |
| − | char prevkey[8] /* Previous key buffer | + | char prevkey[8] /* Previous key buffer */ |
| − | long recno; /* Record no. associated with previous key */ | + | long recno; /* Record no. associated with previous key */ |
| − | char ascii[10]; /* Ascii string buffer | + | char ascii[10]; /* Ascii string buffer */ |
| − | int rc; | + | int rc; /* Return code */ |
| − | ascii[1] = 'D'; /* Indicate the date key | + | ascii[1] = 'D'; /* Indicate the date key */ |
rc = dbpkey(ndx, prevkey, &recno); | rc = dbpkey(ndx, prevkey, &recno); | ||
| − | if (rc = = SUCCESS){ | + | if (rc == SUCCESS){ |
rc = dbkeytoa(prevkey, ascii); | rc = dbkeytoa(prevkey, ascii); | ||
| − | if (rc = = SUCCESS) | + | if (rc == SUCCESS) |
| − | printf("The previous key is %s n", ascii); | + | printf("The previous key is %s \n", ascii); |
else{ | else{ | ||
| − | printf("error number %d n", rc); | + | printf("error number %d \n", rc); |
exit (1); | exit (1); | ||
} | } | ||
Latest revision as of 13:36, 1 May 2009
PURPOSE
convert numeric/data key value to ASCII
SYNOPSIS
#include "dbl.h" int dbkeytoa(key, ascii) <input parameters> char *key; /* Key to be converted */ char ascii[0]; /* Number of decimal places for numeric key */ char ascii[1]; /* Key type: 'D' – for DATE, 'N' – for NUMERIC */ <output parameters> char *ascii; /* Address of an ASCII string representing the converted key value */
NOTE: "ascii" is used in the input and output parameter.
RETURN VALUE
The dbkeytoa() function returns 0 for success, or < 0 if an error occurs. See the section on return code value for a detailed list of return codes.
DESCRIPTION
This function converts a key of type NUMERIC or DATE into a null terminated ASCII string. If the key is of NUMERIC type the user must pass the number of decimal places to the function via the parameter ascii[0]. The key type is specified in the parameter ascii[1]. Function returns an error if the specified type is neither NUMERIC ('N' or 'n') nor DATE ('D' or 'd'). This function is particular useful if the user wants to examine a numeric or date key obtained by the dbckey() or dbnkey() functions.
EXAMPLE
The first example converts an .NDX file numeric key stored in "char key[8]" to an ASCII string which is placed in "char ascii[64]". The converted ASCII string has a precision of 3 decimal places. The converted key is printed on standard output.
#include "dbl.h" char key[8]; /* Key to be converted */ char ascii[64]; /* Buffer for converted key */ int rc; /* Return code */ ascii[0] = 3; /* Specify number of decimal places */ ascii[1] = 'N'; /* Indicate the key is NUMERIC */ rc = dbkeytoa(key, ascii); if (rc == SUCCESS) printf("the key is '%s' \n", ascii); else { printf("error number %d \n", rc); exit (0); }
The second example reads the previous date key from the .NDX file specified by "char *ndx;", converts it from the .NDX date format to the ASCII date format and prints the key on the standard output.
#include "dbl.h" char *ndx; /* .NDX file descriptor */ char prevkey[8] /* Previous key buffer */ long recno; /* Record no. associated with previous key */ char ascii[10]; /* Ascii string buffer */ int rc; /* Return code */ ascii[1] = 'D'; /* Indicate the date key */ rc = dbpkey(ndx, prevkey, &recno); if (rc == SUCCESS){ rc = dbkeytoa(prevkey, ascii); if (rc == SUCCESS) printf("The previous key is %s \n", ascii); else{ printf("error number %d \n", rc); exit (1); } }
