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symcompact(1) [bsd man page]

symcompact(1)						      General Commands Manual						     symcompact(1)

symcompact - string compaction for object files SYNOPSIS
symcompact [ object_name ... ] DESCRIPTION
symcompact reduces the symbol table size of an executable file. This is done by removing unnecessary overlay transfer vectors (text sym- bols beginning with a tilde). In a nonoverlaid program there is no need for both the underscore (_foo) and tilde (~foo) text symbol and only the underscore form is kept. For overlaid programs if the symbol is in the base segment the tilde form is not needed and again only the underscore form is preserved. Running symcompact typically reduces the kernel symbol table size by 250 or so symbols. It is possible to run both symcompact and strcompact to achieve an even higher degree of symbol and string table compaction. The normal sequence is to run symcompact first followed by strcompact. If symcompact runs out of memory it will be necessary to reverse the order and run symcompact a second time - see the BUGS note below. The user must have write permission to the object/executable file. symcompact writes to stderr the count of symbols removed from the symbol table. symcompact exits 0 if successful, and >0 if an error occurred. SEE ALSO
symcompact(1), symorder(1) BUGS
This program can partially negate the benefits of strcompact because multiple references to identical strings cause additional strings to be placed in the string table. Running strcompact again after running this program fixes this problem. The register local symbol type is removed from the executable/object file. Since the debugger really doesn't know how to deal with those symbols this is not much of a loss and saves quite a bit of space both in the symbol table and the string table. symcompact should not be run on .o files that will be passed to the linker. The linker will need the tilde form of the symbol if an over- laid executable is being created. 3rd Berkeley Distribution January 25, 1994 symcompact(1)

Check Out this Related Man Page

syms(4) 						     Kernel Interfaces Manual							   syms(4)

syms - Symbol table SYNOPSIS
#include <sym.h> #include <symconst.h> DESCRIPTION
The symbol table departs from the standard COFF symbol table. The symbol table consists of many tables unbundling information usually found in the one COFF symbol table. The symbol table should be viewed as a handcrafted, network-style database designed for space and access efficiency. The following structures or tables appear in the symbol table: -------------------------------------------------------------------------- Table Contents -------------------------------------------------------------------------- Symbolic header Sizes and locations of all other tables File descriptors Per file locations for other tables Procedure descriptors Frame information and location of procedure information Local symbols Local type, local variable, and scoping informa- tion Local strings String space for local symbols Line numbers Compacted by encoding, contains a line per instruction Relative file desc. Indirection for inter-file symbol access Optimization symbols To be defined Auxiliary symbols Data type information for local and external sym- bols External symbols Global text and data symbols External strings String space for external symbols Dense numbers Index pairs (file, symbol) for compiler use (-oldc only) -------------------------------------------------------------------------- External and local symbols are both represented using the following structure: struct { long iss; /* index into string space */ long value; /* address, size, etc.; depends on sc and st */ unsigned st: 6; /* symbol type (e.g., local, param, etc.) */ unsigned sc: 5; /* storage class (e.g., text, bss, etc.) */ unsigned reserved: 1; unsigned index; /* index to symbol or auxiliary tables */ }; RELATED INFORMATION
ldfcn(4). delim off syms(4)
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