When using embedded SQL in C, the same environment settings as when using the C library (libpq) are required.
Refer to "5.2.1 Environment Settings" in "C Library (libpq)" for information on the environment settings for the library for C.
Additionally, set the following path for the precompiler ecpg:
Linux
symfowareServerClientInstallDir/bin
Windows(R)symfowareServerClientInstallDir\bin