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KLDSYM(2) FreeBSD System Calls Manual KLDSYM(2)
NAME kldsym - look up address by symbol name in a KLD
LIBRARY Standard C Library (libc, -lc)
SYNOPSIS #include <sys/param.h> #include <sys/linker.h>
int kldsym(int fileid, int cmd, void *data);
DESCRIPTION The kldsym() system call returns the address of the symbol specified in data in the module specified by fileid. If fileid is 0, all loaded modules are searched. Currently, the only cmd implemented is KLDSYM_LOOKUP.
The data argument is of the following structure:
struct kld_sym_lookup { int version; /* sizeof(struct kld_sym_lookup) */ char *symname; /* Symbol name we are looking up */ u_long symvalue; size_t symsize; };
The version member is to be set by the code calling kldsym() to sizeof(struct kld_sym_lookup). The next two members, version and symname, are specified by the user. The last two, symvalue and symsize, are filled in by kldsym() and contain the address associated with symname and the size of the data it points to, respectively.
RETURN VALUES The kldsym() function returns the value 0 if successful; otherwise the value -1 is returned and the global variable errno is set to indicate the error.
ERRORS The kldsym() system call will fail if:
[EINVAL] Invalid value in data->version or cmd.
[ENOENT] The fileid argument is invalid, or the specified symbol could not be found.
SEE ALSO kldfind(2), kldfirstmod(2), kldload(2), kldnext(2), kldunload(2), modfind(2), modnext(2), modstat(2), kld(4)
HISTORY The kldsym() system call first appeared in FreeBSD 3.0.
FreeBSD 14.0-RELEASE-p11 October 17, 2016 FreeBSD 14.0-RELEASE-p11