mcs(1) User Commands mcs(1)
mcs - manipulate the comment section of an object file
mcs [-cdpVz] [-a string] [-n name] file...
The mcs command is used to manipulate a section, by default the .com-
ment section, in an ELF object file. It is used to add to, delete,
print, and compress the contents of a section in an ELF object file,
and print only the contents of a section in a COFF object file. mcs
cannot add, delete, or compress the contents of a section that is con-
tained within a segment.
If the input file is an archive (see ar.h(3HEAD)), the archive is
treated as a set of individual files. For example, if the -a option is
specified, the string is appended to the comment section of each ELF
object file in the archive; if the archive member is not an ELF object
file, then it is left unchanged.
mcs must be given one or more of the options described below. It
applies, in order, each of the specified options to each file.
The following options are supported:
-a string Appends string to the comment section of the ELF object
files. If string contains embedded blanks, it must be
enclosed in quotation marks.
-c Compresses the contents of the comment section of the
ELF object files. All duplicate entries are removed.
The ordering of the remaining entries is not disturbed.
-d Deletes the contents of the comment section from the
ELF object files. The section header for the comment
section is also removed.
-n name Specifies the name of the comment section to access if
other than .comment. By default, mcs deals with the
section named .comment. This option can be used to
specify another section. mcs can take multiple -n
options to allow for specification of multiple section
-p Prints the contents of the comment section on the stan-
dard output. Each section printed is tagged by the name
of the file from which it was extracted, using the for-
mat file[member_name]: for archive files and file: for
-V Prints on standard error the version number of mcs.
-z Replaces any SHT_PROGBITS sections with zeros while
retaining the original attributes of the sections.
Example 1: Printing a file's comment section
The following entry
example% mcs -p elf.file
prints the comment section of the file elf.file.
Example 2: Appending a string to a comment section
The following entry
example% mcs -a xyz elf.file
appends string xyz to elf.file's comment section.
/tmp/mcs* temporary files
See attributes(5) for descriptions of the following attributes:
tab() allbox; cw(2.750000i)| cw(2.750000i) lw(2.750000i)|
lw(2.750000i). ATTRIBUTE TYPEATTRIBUTE VALUE AvailabilitySUNWbtool
ar(1), as(1), ld(1), ar.h(3HEAD), elf(3ELF), tmpnam(3C), a.out(4),
When mcs deletes a section using the -d option, it tries to bind
together sections of type SHT_REL and target sections pointed to by the
sh_info section header field. If one is to be deleted, mcs attempts to
delete the other of the pair.
By using the -z option, it is possible to make an object file by remov-
ing the contents of SHT_PROGBITS sections while retaining the object
file's original structure as an ELF file. The need for use of the -z
option is limited. However, the option can be used to deliver an object
file when the contents of SHT_PROGBITS sections are not relevant.
SunOS 5.10 1 Apr 2004 mcs(1)