It was common in Europe (and probably elsewhere) to give a child a common (secular) name for day-to-day use and a "Jewish name" for use in synagogue (e.g., alyah la Torah). This was often done when parents didn't want their child to look different in the secular world while at the same time having a Jewish name to honor a grand-parent.
So assume a father named his son Shlomo at the brit mila, having in mind he would be called Ploni in his day-to-day life and Ploni Shlomo in synagogue.
Are there any halachic issues in this dual name situation where one name is used 99% of the time, and a different name used in synagogue?
Possible halachic issues could be
- Calling someone to the Torah Shlomo (his Jewish name) even if it is nearly never used?
- Calling someone to the Torah Ploni Shlomo when he was named Shlomo?
- What name to use on a ketuba or get?