nm(1)
NAME
nm - print name list of an object file
SYNOPSIS
/usr/ccs/bin/nm [-ACDhlnPprRsTuVv] [-efox] [-g | -u] [-
t format] file...
/usr/xpg4/bin/nm [-ACDhlnPprRsTuVv] [-efox] [-g | -u] [-
t format] file...
DESCRIPTION
The nm utility displays the symbol table of each ELF object
file that is specified by file.
If no symbolic information is available for a valid input
file, the nm utility will report that fact, but not consider
it an error condition.
OPTIONS
The output of nm may be controlled using the following
options:
-A Writes the full path name or library name of an object
on each line.
-C Demangles C++ symbol names before printing them out.
-D Displays the SHT_DYNSYM symbol information. This is
the symbol table used by ld.so.1 and is present even
in stripped dynamic executables. By default, the
SHT_SYMTAB symbol table is displayed.
-e See NOTES below.
-f See NOTES below.
-g Writes only external (global) symbol information.
-h Does not display the output heading data.
-l Distinguishes between WEAK and GLOBAL symbols by
appending a * to the key letter for WEAK symbols.
-n Sorts external symbols by name before they are
printed.
-o Prints the value and size of a symbol in octal instead
of decimal (equivalent to -t o).
-p Produces easy to parse, terse output. Each symbol name
is preceded by its value (blanks if undefined) and one
of the letters:
A Absolute symbol.
B bss (uninitialized data space) symbol.
C COMMON symbol.
D Data object symbol.
F File symbol.
N Symbol has no type.
L Thread-Local storage symbol.
S Section symbol.
T Text symbol.
U Undefined.
If the symbol's binding attribute is:
LOCAL The key letter is lower case.
WEAK The key letter is upper case. If the -l modifier
is specified, the upper case key letter is fol-
lowed by a *
GLOBAL
The key letter is upper case.
-P Writes information in a portable output format, as
specified in Standard Output.
-r Prepends the name of the object file or archive to
each output line.
-R Prints the archive name (if present), followed by the
object file and symbol name. If the -r option is also
specified, this option is ignored.
-s Prints section name instead of section index.
-t format
Writes each numeric value in the specified format. The
format is dependent on the single character used as
the format option-argument:
d The offset is written in decimal (default).
o The offset is written in octal.
x The offset is written in hexadecimal.
-T See NOTES below.
/usr/ccs/bin/nm
-u Prints undefined symbols only.
/usr/xpg4/bin/nm
-u Prints long listing for each undefined symbol. See
OUTPUT below.
-v Sorts external symbols by value before they are
printed.
-V Prints the version of the nm command executing on the
standard error output.
-x Prints the value and size of a symbol in hexadecimal
instead of decimal (equivalent to -t x).
Options may be used in any order, either singly or in combi-
nation, and may appear anywhere in the command line. When
conflicting options are specified (such as -v and -n, or -o
and -x) the first is taken and the second ignored with a
warning message to the user. (See -R for exception.)
OPERANDS
The following operand is supported:
file A path name of an object file, executable file or
object-file library.
OUTPUT
This section describes the nm utility's output options.
Standard Output
For each symbol, the following information will be printed:
Index The index of the symbol. (The index appears in brack-
ets.)
Value The value of the symbol is one of the following:
o A section offset for defined symbols in a relo-
catable file.
o Alignment constraints for symbols whose section
index is SHN_COMMON.
o A virtual address in executable and dynamic
library files.
Size The size in bytes of the associated object.
Type A symbol is of one of the following types:
NOTYPE
No type was specified.
OBJECT
A data object such as an array or variable.
FUNC A function or other executable code.
REGI A register symbol (SPARC only).
SECTION
A section symbol.
FILE Name of the source file.
COMMON
An uninitialized common block.
TLS A variable associated with Thread-Local storage.
Bind The symbol's binding attributes.
LOCAL symbols
Have a scope limited to the object file contain-
ing their definition.
GLOBAL symbols
Are visible to all object files being combined.
WEAK symbols
Are essentially global symbols with a lower pre-
cedence than GLOBAL.
Other A field reserved for future use, currently containing
0.
Shndx Except for three special values, this is the section
header table index in relation to which the symbol is
defined. The following special values exist:
ABS Indicates the symbol's value will not change
through relocation.
COMMON
Indicates an unallocated block and the value
provides alignment constraints.
UNDEF Indicates an undefined symbol.
Name The name of the symbol.
Object Name
The name of the object or library if -A is specified.
If the -P option is specified, the previous information is
displayed using the following portable format. The three
versions differ depending on whether -t d, -t o, or -t x was
specified, respectively:
"%s%s %s %d %d\n", library/object name, name, type, value,
size "%s%s %s %o %o\n", library/object name, name , type,
value , size "%s%s %s %x %x\n", library/object name, name,
type, value, size
where library/object name is formatted as follows:
o If -A is not specified, library/object name is an
empty string.
o If -A is specified and the corresponding file operand
does not name a library:
"%s: ", file
o If -A is specified and the corresponding file operand
names a library. In this case, object file names the
object file in the library containing the symbol being
described:
"%s[%s]: ", file, object file
If -A is not specified, then if more than one file operand
is specified or if only one file operand is specified and it
names a library, nm will write a line identifying the object
containing the following symbols before the lines containing
those symbols, in the form:
o If the corresponding file operand does not name a
library:
"%s:\n", file
o If the corresponding file operand names a library; in
this case, object file is the name of the file in the
library containing the following symbols:
"%s[%s]:\n", file, object file
If -P is specified, but -t is not, the format is as if -t x
had been specified.
ENVIRONMENT VARIABLES
See environ(5) for descriptions of the following environment
variables that affect the execution of nm: LANG, LC_ALL,
LC_COLLATE, LC_CTYPE, LC_MESSAGES, and NLSPATH.
EXIT STATUS
The following exit values are returned:
0 Successful completion.
>0 An error occurred.
ATTRIBUTES
See attributes(5) for descriptions of the following attri-
butes:
/usr/ccs/bin/nm
____________________________________________________________
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
|_____________________________|_____________________________|
| Availability | SUNWbtool |
|_____________________________|_____________________________|
/usr/xpg4/bin/nm
____________________________________________________________
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
|_____________________________|_____________________________|
| Availability | SUNWxcu4 |
|_____________________________|_____________________________|
| Interface Stability | Standard |
|_____________________________|_____________________________|
SEE ALSO
ar(1), as(1), dump(1), ld(1), ld.so.1(1), ar(3HEAD),
a.out(4), attributes(5), environ(5), standards(5)
NOTES
The following options are obsolete because of changes to the
object file format and will be deleted in a future release.
-e Prints only external and static symbols. The symbol
table now contains only static and external symbols.
Automatic symbols no longer appear in the symbol
table. They do appear in the debugging information
produced by cc -g, which may be examined using
dump(1).
-f Produces full output. Redundant symbols (such as
.text, .data, and so forth), which existed previously,
do not exist and producing full output will be identi-
cal to the default output.
-T By default, nm prints the entire name of the symbols
listed. Since symbol names have been moved to the last
column, the problem of overflow is removed and it is
no longer necessary to truncate the symbol name.
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