NAME

mcs − Manipulates object file comment sections

SYNOPSIS

mcs [−v] [−V] [[−a|r|R  data] | [−D key] | [−d] ] [−t tag] [−g flags] [−p] obj1...objN

OPTIONS

−a data
Add a new subsection or append to existing subsection data. By default, the data is treated as a character string and appended to the generic string space subsection. Use −t to specify a subsection. 

−dDelete a subsection. Use −t to specify the subsection that you want to delete. 

−D key
Delete one entry within a subsection. Use −t to specify the subsection that this operation applies to. Currently, this option can only be used with the system subsections TAGDESC and TOOLVER. 

−g flags
Set tag descriptor flags for a subsection. Use −t to specify the subsection. If flag settings already exist for this tag value, they are overwritten by the new settings. 

−pPrint a subsection or the entire comment section. By default, the whole section is dumped. Use −t to specify a subsection. By default, raw data is dumped in hexadecimal. Special formatting can be used for system-defined subsections. 

Use with −v to view contents symbolically. 

This option produces the same output as odump −cm. Use odump −j to view compact relocations data stored in the comment section. 

−r data
Replace subsection data. Use −t to specify the subsection that you want to replace. The same data interpretation applies to both −r and −a. 

−R data
Replace one entry of a subsection with the given data. Use −t to specify the subsection that this applies to. Currently, this option can only be used with the system subsections TAGDESC and TOOLVER. 

−t tag
Specify subsection. Within an object, a tag is a unique identifier; only one subsection is permitted of each tag type.

−vProduce verbose output. Can be used with −p. 

−VPrint version information for the mcs tool. 

OPERANDS

dataCharacter string.  Character strings containing white space must be enclosed in quotes. 

For certain subsections, specially formatted data is accepted. See Special Sections for more information. 

keyUnique identifier for an entry within a subsection. See Special Sections for more information. 

tagAn unsigned integer value or a system-defined tag name. 

flagsComma-separated tag descriptor flag names. See Special Sections for more information. 

objA Tru64 UNIX object file that contains a comment section header. Archive files are not supported. The object file can be a .o file, an executable, or a shared library. It can be either compressed or uncompressed. 

DESCRIPTION

The mcs command allows users to perform operations on the comment section (.comment) of Compaq (e)COFF object files. The comment section of an object can contain information such as the “ident” string from a source file and other information used by components of the Tru64 UNIX development environment. Users can optionally add their own information to the comment section by using the mcs tool. 

Special Symbols

Definitions for symbols related to the comment section are located in /usr/include/scncomment.h. The symbols recognized by mcs are shortened forms of the names defined in the header file.  The symbols consist of the names of system-defined tags and tag descriptor flags. 

System-defined tag names can be used with the −t option to specify a subsection. These tags are:

CMSTAMP
COMPACT_RLC
STRSPACE
TAGDESC
IDENT
TOOLVER

Tag descriptor flag names can be used with the −g option to specify how other tools should treat a specified subsection. The flag names recognized by mcs are:

KEEP
STRIP
LSTRIP
APPEND
CHOOSE
DELETE
ERRMULT
ERROR
COPY

See Special Sections for more information on the TAGDESC and TOOLVER subsections. 

Special Sections

Processing of the TAGDESC and TOOLVER subsections differs from other sections due to the following factors:

     1.The −R and −D options can be used for per-entry operations. 

     2.The data entry format is unique. 

TAGDESC Processing
System tools that create or modify objects rely on tag descriptor flags in the TAGDESC section to know how to process subsections that are not recognized by the tool. This allows new subsection types to be added without requiring changes to system tools that control how they process the new subsections. 

Three sets of flags are supported:

The “strip” flags tell the linker or stripping tools what subsections belong in a stripped or locally-stripped object:

       •KEEP means do not strip. 

       •STRIP means delete if removing the symbol table. 

       •LSTRIP means delete if removing local symbol information. 

The “combine” flags tell tools such as the linker and mcs how to combine data from multiple input subsections of the same type:

       •APPEND means to concatenate raw data for each subsection. 

       •CHOOSE means to choose one (random) subsection’s data. 

       •DELETE tells the tools that this subsection does not belong in an output object. 

       •ERRMULT means raise an error if multiple instances of the tag value are found. 

       •ERROR means raise an error if the tag value identifies an unknown subsection type. 

The “modify” flags tell a tool that is modifying a single object what to do with subsections it does not understand:

       •COPY means output a subsection identical to the one found in the input object. 

       •DELETE means do not output the subsection. 

       •ERROR means raise an error if a subsection of this type is encountered. 

One value from each set is defined for each subsection. The default flag settings are KEEP, APPEND, COPY. 

Flags are specified symbolically on the command line. The accepted format is a comma-separated list of three flag names with no white space.  For example, the default flag setting for a subsection with the tag TAG# is specified as follows:

mcs -t TAG# -gKEEP,APPEND,COPY obj

The key for a TAGDESC entry is the tag value being described. 

TOOLVER Processing
The TOOLVER subsection accepts data of the form: tool_name,tool_version_number,version_string

The variables tool_name and version_string are character strings, and tool_version_number is a numeric value. For example, to add tool version information for a program named mytool, the command is:

mcs −t TOOLVER −a "mytool,0,\"Beta, 1/1/99\ obj

This creates a new entry for the tool named mytool in the TOOLVER subsection. To update this entry, use the −R option:

mcs −t TOOLVER −R "mytool,1,\"SSB, 1/1/99\ obj

Note that double quotes have to be passed through the shell for strings containing white space or commas. Make sure that the separator commas have no spaces around them. 

The key for the TOOLVER entry is the tool name. 

EXAMPLES

The comment section of an executable file might appear as follows:

% mcs -pv objname

   Tag            Length      Value     Flags: Strip Combine Modify
   CMSTAMP        0x0         0x0              KEEP CHOOSE COPY
   COMPACT_RLC    0x208       0x30             STRIP DELETE DELETE
        --- freeform data ---
                Use odump -j to view compact relocations.
        ---- end data ---
   END            0x0         0x0              KEEP CHOOSE COPY

If you want to delete compact relocations:

% mcs -d -t COMPACT_RLC objname

If you want to add a subsection and specify flags for it:

% mcs -a DATA -t10 -g STRIP,APPEND,COPY objname

The new subsection, identified by a tag value of 10, contains the string “DATA” in its associated freeform data. The flag settings indicate that the section should be stripped if the symbol table is removed, have data appended if objects with this section are linked or otherwise combined, and left unchanged by an object modifier. 

ENVIRONMENT VARIABLES

The following environment variables affect the execution of mcs:

TMPDIR
If set, this path is used for the creation of a temporary file. A temporary file is used if an input object is compressed.

SEE ALSO

Commands:  odump(1)