I am trying to connect to a PostgreSQL database using the R ODBC drivers in RStudio. For some reason, the drivers are not being detected by R:
$ Rscript -e 'odbc::odbcListDrivers()'
[1] name      attribute value    
<0 rows> (or 0-length row.names)
Even though as far as I can tell, they are correctly installed (using homebrew):
$ brew list
freetds     gettext     git     icu4c       libtool     openssl     pcre2       pkg-config  
postgresql  psqlodbc    readline    sqlite      sqliteodbc  unixodbc
$ odbcinst -j
unixODBC 2.3.6
DRIVERS............: /etc/odbcinst.ini
SYSTEM DATA SOURCES: /etc/odbc.ini
FILE DATA SOURCES..: /etc/ODBCDataSources
USER DATA SOURCES..: /Users/barthf/.odbc.ini
SQLULEN Size.......: 8
SQLLEN Size........: 8
SQLSETPOSIROW Size.: 8
$ cat /etc/odbcinst.ini
[PostgreSQL Driver]
Driver          = /usr/local/lib/psqlodbcw.so
[SQLite Driver]
Driver          = /usr/local/lib/libsqlite3odbc.dylib
$ ls /usr/local/lib/ | grep odbc.*so$
libsqlite3odbc.so
libtdsodbc.0.so
libtdsodbc.so
psqlodbca.so
psqlodbcw.so
I am running on:
R version 3.4.2 (2017-09-28)
Platform: x86_64-apple-darwin15.6.0 (64-bit)
Running under: OS X El Capitan 10.11.6
locale:
[1] en_US.UTF-8/en_US.UTF-8/en_US.UTF-8/C/en_US.UTF-8/en_US.UTF-8
attached base packages:
[1] stats     graphics  grDevices utils     datasets  methods   base     
other attached packages:
[1] DBI_1.0.0  odbc_1.1.6
loaded via a namespace (and not attached):
 [1] Rcpp_0.12.18      dbplyr_1.1.0      compiler_3.4.2    pillar_1.2.3      later_0.7.1       plyr_1.8.4       
 [7] bindr_0.1.1       base64enc_0.1-3   tools_3.4.2       digest_0.6.12     bit_1.1-12        jsonlite_1.5     
[13] tibble_1.4.2      nlme_3.1-131      lattice_0.20-35   pkgconfig_2.0.2   rlang_0.2.2       psych_1.7.8      
[19] shiny_1.0.5       rstudioapi_0.7    parallel_3.4.2    RPostgreSQL_0.6-2 yaml_2.1.14       bindrcpp_0.2.2   
[25] stringr_1.2.0     httr_1.3.1        dplyr_0.7.5       sparklyr_0.8.4    hms_0.4.2         rprojroot_1.2    
[31] bit64_0.9-7       grid_3.4.2        tidyselect_0.2.4  glue_1.2.0        R6_2.2.2          foreign_0.8-69   
[37] tidyr_0.7.2       reshape2_1.4.2    purrr_0.2.5       blob_1.1.1        magrittr_1.5      backports_1.1.1  
[43] promises_1.0.1    htmltools_0.3.6   mnormt_1.5-5      assertthat_0.2.0  mime_0.5          xtable_1.8-2     
[49] httpuv_1.4.0      stringi_1.1.5     lazyeval_0.2.1    broom_0.4.2    
For some reason unknown to me, the RPostgreSQL::PostgreSQL() driver works fine. However I want to use the ODBC driver so I can make use of the RStudio Connections feature. When I try to use RStudio to create a New Connection the dialog window only shows options for connecting to Livy and Spark. 
As suggested, here is the attempted connection code:
Using ODBC:
> con <- DBI::dbConnect(odbc::odbc(),
+                       driver = "PostgreSQL Driver",
+                       database = "postgres",
+                       UID    = rstudioapi::askForPassword("Database user"),
+                       PWD    = rstudioapi::askForPassword("Database password"),
+                       host = "localhost",
+                       port = 5432) ## returns error below
Error: nanodbc/nanodbc.cpp:950: 01000: [unixODBC][Driver Manager]Can't open lib 'PostgreSQL Driver' : file not found 
Using RPostgreSQL:
con <- DBI::dbConnect(RPostgreSQL::PostgreSQL(),
+   dbname = "postgres",
+   user    = rstudioapi::askForPassword("Database user"),
+   password    = rstudioapi::askForPassword("Database password"),
+   host = "localhost",
+   port = 5432) ## works fine
Any thoughts why the R ODBC drivers do not seem to work? Any suggestions on things that I can try here?
 
    