I need to fetch strings from a database with ECPG and then sort them in
C. Here is one of my failed attempts:
###########################
int main(int argc, char *argv[]) {
int maxlen=20;
long nrec;
EXEC SQL BEGIN DECLARE SECTION;
varchar filenms[][maxlen]=NULL;
char dbnm[50];
EXEC SQL END DECLARE SECTION;
sprintf(dbnm,"%s",argv[1]);
EXEC SQL CONNECT TO :dbnm;
EXEC SQL SELECT filenm INTO :filenms FROM beamdata;
nrec = sqlca.sqlerrd[2]; /* Returns number of rows retrieved */
EXEC SQL COMMIT;
EXEC SQL DISCONNECT;
qsort(filenms, nrec, maxlen*sizeof(char), scmp);
free(filenms);
return 0;
}
static int scmp( const void *sp1, const void *sp2 )
{
return( strcmp(*(char **)sp1, *(char **)sp2) );
}
###########################
It compiles ok, but I get garbage in variable filenms. If I change the
declaration of filenms to:
char **filenms=NULL;
the SQL query returns strings ok. But the strings have variable length,
and I need to specify one length in qsort, so it won't work. Another
attempt to try to specify string length:
char (*filenms)[maxlen]=NULL;
Won't compile, ECPG doesn't accept this syntax. Well, and strcmp crashes
(segmentation fault) in function scmp regardless what I try. Not SQL
error, I know, but if anybody can tell why I'd be grateful.
Any suggestions?
Thanks,
Poul Jensen
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