HelenOS sources

U_HOME_ARROW       62 common/include/str.h #define U_HOME_ARROW   0x21f1
U_HOME_ARROW       62 kernel/generic/common/include/str.h #define U_HOME_ARROW   0x21f1
U_HOME_ARROW       62 uspace/lib/c/common/include/str.h #define U_HOME_ARROW   0x21f1
U_HOME_ARROW       62 uspace/lib/posix/include/common/str.h #define U_HOME_ARROW   0x21f1

HelenOS homepage, sources at GitHub