AIX /bin/echo doesn’t support -n.
AIX echo and OS X /bin/echo support \c to prevent a trailing newline but linux echo (bash builtin and /bin/echo) don’t support it unless you also use the -e flag (which is not support by AIX /bin/echo or OS X sh or /bin/echo).
The BSD echo man page suggests using printf to avoid trailing newline, which is available on linux, OS X, and AIX.
