[llvm] [SystemZ][z/OS] Query if a file is text and set the text flag accordingly (PR #109664)

[kadir çetinkaya via llvm-commits]

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@@ -52,6 +52,12 @@ std::error_code restorezOSStdHandleAutoConversion(int FD);
 /// \brief Set the tag information for a file descriptor.
 std::error_code setzOSFileTag(int FD, int CCSID, bool Text);
 
+// Get the the tag ccsid for a file name or a file descriptor.
+ErrorOr<__ccsid_t> getzOSFileTag(const char *FileName, const int FD = -1);
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kadircet wrote:

there are no external callers for this function, can we keep it internal?

https://github.com/llvm/llvm-project/pull/109664