gdb: The F Request Packet
E.13.3 The 'F' Request Packet
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The 'F' request packet has the following format:
'FCALL-ID,PARAMETER...'
CALL-ID is the identifier to indicate the host system call to be
called. This is just the name of the function.
PARAMETER... are the parameters to the system call. Parameters are
hexadecimal integer values, either the actual values in case of
scalar datatypes, pointers to target buffer space in case of
compound datatypes and unspecified memory areas, or pointer/length
pairs in case of string parameters. These are appended to the
CALL-ID as a comma-delimited list. All values are transmitted in
ASCII string representation, pointer/length pairs separated by a
slash.