stio - routines that provide a binary read/write interface
to the symbol table
char how ); long st_readst(
long flags ); void st_writebinary(
long flags ); void st_writest(
long flags );
The CHDRR structure (see stcu(3)) represents a symbol
table in memory. A new CHDRR can be created by reading a
symbol table from disk. The st_readbinary() and
st_readst() routines read a symbol table from disk.
The st_readbinary() routine takes the file name of the
symbol table and assumes the symbol table header HDRR
occurs at the beginning of the file. The st_readst() routine
assumes that its file number references a file positioned
at the beginning of the symbol table header and
that the filebase parameter specifies where the object or
symbol table file is based (for example, nonzero for
The second parameter to the read routines can be `r' for
read only or `a' for appending to the symbol table. Existing
local symbol, line, procedure, auxiliary, optimization,
and local string tables cannot be appended. If they
did not exist on disk, they can be created. This restriction
stems from the allocation algorithm for those symbol
table sections when read in from disk and follows the
standard pattern for building the symbol table.
The symbol table can be read incrementally. If pchdr is
zero, st_readst() assumes that no symbol table has been
read yet; therefore, it reads in the symbol table header
and file descriptors. The flags argument is a bit mask
that defines what other tables should be read. St_p* constants
for each table can be ORed. If flags equals -1, all
tables are read. If pchdr is set, the tables specified by
flags are added to the tables that have already been read.
The value of pchdr can be gotten from st_current_pchdr()
Line number entries are encoded on disk, and the read routines
expand them to longs.
If the version stamp is out of date, a warning message is
issued to stderr. If the magic number in the HDRR is
incorrect, st_error() is called. All other errors cause
the read routines to read nonzero; otherwise, a zero is
The st_writebinary() and st_writest() routines are symmetric
to the read routines, excluding the how and pchdr
parameters. The flags parameter is a bit mask that defines
what table should be written. St_p* constants for each
table can be ORed. If flags equals -1, all tables are
The write routines write sections of the table in the
approved order, as specified in the link editor (ld) specification.
Line numbers are compressed on disk.
The write routines start all sections of the symbol table
on four-byte boundaries.
If the write routines encounter an error, st_error() is
called. After writing the symbol table, further access to
the table by other routines is undefined.
stcu(3), stfe(3), stfd(3)
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