Postgres and C

The libpq library makes postgres easy to use in C programs. My only issue with it is that it is too "low level" for most uses. In other contexts I have enjoyed using the postgres command line client, psql, in shell scripts. One can pipe a query through psql and let the result flow through to stdout or to a file or capture the output in a variable for further processing. No knowledge of internals is required.

I desired to use postgres with C while enjoying the same "ease of use". I also wanted to be able to run many queries with one connection. These wrappers provide most of that.

They are not nearly perfect, but usable.

Wrapper Functions

• database_init opens a connection to the database, provides that it be closed on exit, returns 0 on success.
• query_to_file accepts a query and a file as input, returns 0 on success.
• query_to_stdout accepts a query as input, passes that along with sdtout to query_to_file and returns the result.
• get_query_fields accepts a query and other params as input. A pointer to the results is returned, and a return code is set.

Possible Improvements

The database_init function could take a connection string instead of just a database name as a parameter. This assumes more knowledge on the part of the user.

The get_query_fields funtion could be altered to return 0 on success which would make it more consistent. Done.

Other improvements?

The code

Warts and all View at your own peril.