Try hdl.libs.change_key_in_dict_file(p, key, new_value) in mode=1 option.

tools/oneclick/base/hdl_config.py

@@ -186,6 +186,12 @@ class HdlConfig:
         return tech_dict
     
 if __name__ == '__main__':
+    # Mode
+    # 0 = Read dictionary info from all HDL tool and library configuration files and derive the compile order
+    # 1 = Change a key value in all hdllib.cfg dict files
+    mode = 0
+    
+    if mode==0:   
         # Read the dictionary info from all HDL tool and library configuration files in the current directory and the sub directories
         libRootDir = 'RADIOHDL'
         #libRootDir = 'UNB'
@@ -236,3 +242,11 @@ if __name__ == '__main__':
             print 'derive_lib_order = ', hdl.derive_lib_order(hdl.derive_all_use_libs('unb_common'))
             print 'derive_lib_order = ', hdl.derive_lib_order(hdl.derive_all_use_libs('unb_minimal'))
     
+    if mode==1:
+        key = 'build_synth_dir'
+        new_value = '$HDL_BUILD_DIR'
+        # Read the dictionary info from all HDL tool and library configuration files in the current directory and the sub directories
+        libRootDir = 'RADIOHDL'
+        hdl = HdlConfig(libRootDir=os.environ[libRootDir], toolRootDir=os.path.expandvars('$RADIOHDL/tools'), libFileName='hdllib.cfg', toolFileName='hdltool.cfg')
+        for p in hdl.libs.filePathNames:
+             hdl.libs.change_key_in_dict_file(p, key, new_value)