For example, the following source code:

int dcmd(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv) { uint_t opt_v = FALSE; const char *opt_s = NULL; if (mdb_getopts(argc, argv, 'v', MDB_OPT_SETBITS, TRUE, &opt_v, 's', MDB_OPT_STR, &opt_s, NULL) != argc) return (DCMD_USAGE); /* ... */ }

demonstrates how mdb_getopts() might be used in a dcmd to accept a boolean option "-v" that sets the opt_v variable to TRUE, and an option "-s" that accepts a string argument that is stored in the opt_s variable. The mdb_getopts() function also automatically issues warning messages if it detects an invalid option letter or missing option argument before returning to the caller. The storage for argument strings and the argv array is automatically garbage-collected by the debugger upon completion of the dcmd.

mdb_strtoull()

u_longlong_t mdb_strtoull(const char *s);

Convert the specified string s to an unsigned long long representation. This function is intended for use in processing and converting string arguments in situations where mdb_getopts() is not appropriate. If the string argument cannot be converted to a valid integer representation, the function fails by printing an appropriate error message and aborting the dcmd. Therefore, error checking code is not required. The string can be prefixed with any of the valid base specifiers (0i, 0I, 0o, 0O, 0t, 0T, 0x, or 0X); otherwise, it is interpreted using the default base. The function will fail and abort the dcmd if any of the characters in s are not appropriate for the base, or if integer overflow occurs.

mdb_alloc(), mdb_zalloc() and mdb_free()

void *mdb_alloc(size_t size, uint_t flags);
void *mdb_zalloc(size_t size, uint_t flags);
void mdb_free(void *buf, size_t size);

mdb_alloc() allocates size bytes of debugger memory and returns a pointer to the allocated memory. The allocated memory is at least double-word aligned, so it can hold any C data structure. No greater alignment can be assumed. The flags parameter should be the bitwise OR of one or more of the following values:

UM_NOSLEEP	If sufficient memory to fulfill the request is not immediately available, return NULL to indicate failure. The caller must check for NULL and handle this case appropriately.
UM_SLEEP	If sufficient memory to fulfill the request is not immediately available, sleep until such time as the request can be fulfilled. As a result, UM_SLEEP allocations are guaranteed to succeed. The caller need not check for a NULL return value.
UM_GC	Garbage-collect allocation automatically at the end of this debugger command. The caller should not subsequently call mdb_free() on this block, as the debugger will take care of de-allocation automatically. All memory allocation from within a dcmd must use UM_GC so that if the dcmd is interrupted by the user, the debugger can garbage-collect the memory.

mdb_zalloc() is like mdb_alloc(), but the allocated memory is filled with zeroes before returning it to the caller. No guarantees are made about the initial contents of memory returned by mdb_alloc(). mdb_free() is used to free previously allocated memory (unless it was allocated UM_GC). The buffer address and size must exactly match the original allocation. It is not legal to free only a portion of an allocation with mdb_free(). It is not legal to free an allocation more than once. An allocation of zero bytes always returns NULL; freeing a NULL pointer with size zero always succeeds.

mdb_printf()

void mdb_printf(const char *format, ...);

Print formatted output using the specified format string and arguments. Module writers should use mdb_printf() for all output, except for warning and error messages. This function automatically triggers the built-in output pager when appropriate. The mdb_printf() function is similar to printf(3C), with certain exceptions: the %C, %S, and %ws specifiers for wide character strings are not supported, the %f floating-point format is not supported, the %e, %E, %g, and %G specifiers for alternative double formats produce only a single style of output, and precision specifications of the form %.n are not supported. The list of specifiers that are supported follows:

Flag Specifiers

Field Width Specifiers

Integer Specifiers

Terminal Attribute Specifiers

If standard output for the debugger is a terminal, and terminal attributes can be obtained by the terminfo database, the following terminal escape constructs can be used:

If no terminal information is available, each terminal attribute construct is ignored by mdb_printf(). For more information on terminal attributes, see terminfo(4). The available terminfo attributes are: