[tools-linking] Interposing single library symbol still requires -z interpose?

[ольга крыжановская]

Do I have to use -z interpose when I link a shared library if it
wishes to interpose a single libc symbol or can I accomplish this via
a linker mapfile?
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 `'-..-| /     Solaris/BSD//C/C++ programmer   \ |-..-'`
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