interrogate-symbols is designed to find why symbols are left in the image even though they should not be. Since keeping information in the image would itself keep symbols, the facility has as little functionality as possible. The result is a non-intuitive interface, and you should be ready for this. You are encouraged to try other methods first. In particular, you might considercontacting Xanalys Lisp Support first.
interrogate-symbols to work, the keyword
:interrogate-symbols should be passed to
deliver , with the value
t. This loads the interrogate symbol facility. and in addition sets up the image so that on startup it checks if the command line contains
-interrogate-symbols . If it does, the image first does symbol interrogation, and then goes on to the application.
Symbol interrogation starts by building an internal table of reverse pointers, during which the image prints some messages about its progress. When it finishes, it prompts :
Enter Symbol >
The input is read one line at a time. Each line is interpreted as a single string, as follows:
#\:, and does not starts with
#\+, it is a symbol name. The string is used as the argument to
find-symbol(in the current package). Note the string is as it is, so it must not contain escape characters or leading or trailing spaces, and must be in the right case. for example, the symbol that is printed
must be entered:
[ omitting the escape characters
#\\ ] and to find the symbol
CAR , you must enter
CAR , and not
car. #\ : characters after the first one (or the first pair) are taken as part of the symbol.
If the symbol is found, the image prints a list, when the car is the symbol, the second elemnt is a list of interesting symbols that points to that symbol (possibly through uninteresting symbols), and the third element is a list of symbols that points to the symbol directly. A symbol B points to symbol B directly when there is a chain of pointers from A to B which does not go thorugh another symbol.
An interesting symbol is a symbol in another package, or a symbol from the same package which is pointed to by a symbol from another package. The idea is that the interesting symbols are the symbols that are most likely to be worth a further investigation.
Both the second and the third element may be the symbol
:MANY rather than a list, if there are more the
30 ) of them.
#\:character or a pair of
#\:characters, and there characters after it, it a package name followed by a symbol name. The characters up to the first
#\:are used to search for the package. If it is found, it skips the
#\:, and if the following characters are
#\:it skips them, too. The rest of the string is then used as a symbol name. Like in 1. above, both the package name and the symbol name must match exactly the actual package and symbol name. The output is the same as in 1.
#\+followed by a string as in 1. or 2., then the symbol is found as in 1. or 2. Instead of looking for symbols that point to it, the image builds a tree of rereverse pointers starting from the symbol, going to depth
sys::*check-symbol-depth*. In the tree, the
caris an object and the
cdris a list of pointers to it. Each pointer may be a single object (if it has reached the depth limit, or found an object that is already in the tree), or a recursive tree. The tree may be quite extensive
#\:character (or pair) is the last character in the string, than the line specifies a package name. If the string does not start with a
#\+, the image prints each symbol from _other_ package that points (as defined in(1) above) to symbols in the package, followed by a list of the symbol in the package that it points to. To construct is this it has to check the reverse pointers from all the symbols in the package, which may take a long time if the package contains many symbols.
This option is specially useful, in conjunction with the
:smash-packages-symbols keyword to
deliver , to find why a package that should have gone is left in the image.
#\:as in (4) above, but starts with
#\+, then the rest of the string is treated as in (4), but the image simply prints for each the symbol in the package the same information that (1) prints for a single symbol.