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9.4. Accessing string data at a probe point

The following functions provide methods to access string data at a probe point.

9.4.1. kernel_string

General syntax: 
kernel_string:string (addr:long)
Copies a string from kernel space at a given address. The validation of this address is only partial.

9.4.2. user_string

General syntax: 
user_string:string (addr:long)
This function copies a string from user space at a given address. The validation of this address is only partial. In rare cases when userspace data is not accessible, this function returns the string <unknown>.

9.4.3. user_string2

General syntax: 
user_string2:string (addr:long, err_msg:string)
This function is similar to user_string, (Section Section 9.4.2, “user_string”) but allows passing an error message as an argument to be returned if userspace data is not available.

9.4.4. user_string_warn

General syntax: 
user_string_warn:string (addr:long)
This function copies a string from userspace at given address. It prints a verbose error message on failure.

9.4.5. user_string_quoted

General syntax: 
user_string_quoted:string (addr:long)
This function copies a string from userspace at given address. Any ASCII characters that are not printable are replaced by the corresponding escape sequence in the returned string.