NM(1) (Software Generation System Utilities) NM(1)
NAME
nm - print name list of common object file
SYNOPSIS
nm [-oxhvnefurpVT] filename ...
DESCRIPTION
The nm command displays the symbol table of each common
object file, filename. Filename may be a relocatable or
absolute common object file; or it may be an archive of
relocatable or absolute common object files. For each
symbol, the following information will be printed:
Name The name of the symbol.
Value Its value expressed as an offset or an address
depending on its storage class.
Class Its storage class.
Type Its type and derived type. If the symbol is an
instance of a structure or of a union then the
structure or union tag will be given following the
type (e.g., struct-tag). If the symbol is an
array, then the array dimensions will be given
following the type (e.g., char[ n ][ m ] ). Note
that the object file must have been compiled with
the -g option of the cc(1) command for this
information to appear.
Size Its size in bytes, if available. Note that the
object file must have been compiled with the -g
option of the cc(1) command for this information to
appear.
Line The source line number at which it is defined, if
available. Note that the object file must have
been compiled with the -g option of the cc(1)
command for this information to appear.
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NM(1) (Software Generation System Utilities) NM(1)
Section For storage classes static and external, the object
file section containing the symbol (e.g., text,
data or bss).
The output of nm may be controlled using the following
options:
-o Print the value and size of a symbol in octal
instead of decimal.
-x Print the value and size of a symbol in hexadecimal
instead of decimal.
-h Do not display the output header data.
-v Sort external symbols by value before they are
printed.
-n Sort external symbols by name before they are
printed.
-e Print only external and static symbols.
-f Produce full output. Print redundant symbols
(.text, .data, .lib, and .bss), normally
suppressed.
-u Print undefined symbols only.
-r Prepend the name of the object file or archive to
each output line.
-p Produce easily parsable, terse output. Each symbol
name is preceded by its value (blanks if undefined)
and one of the letters U (undefined), A (absolute),
T (text segment symbol), D (data segment symbol), S
(user defined segment symbol), R (register symbol),
F (file symbol), or C (common symbol). If the
symbol is local (non-external), the type letter is
in lower case.
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NM(1) (Software Generation System Utilities) NM(1)
-V Print the version of the nm command executing on
the standard error output.
-T By default, nm prints the entire name of the
symbols listed. Since object files can have
symbols names with an arbitrary number of
characters, a name that is longer than the width of
the column set aside for names will overflow its
column, forcing every column after the name to be
misaligned. The -T option causes nm to truncate
every name which would otherwise overflow its
column and place an asterisk as the last character
in the displayed name to mark it as truncated.
Options may be used in any order, either singly or in
combination, and may appear anywhere in the command line.
Therefore, both nm name -e -v and nm -ve name print the
static and external symbols in name, with external symbols
sorted by value.
FILES
TMPDIR/* temporary files
TMPDIR is usually /usr/tmp but can be redefined by setting
the environment variable TMPDIR [see tempnam() in
tmpnam(3S)].
BUGS
When all the symbols are printed, they must be printed in
the order they appear in the symbol table in order to
preserve scoping information. Therefore, the -v and -n
options should be used only in conjunction with the -e
option.
SEE ALSO
as(1), cc(1), ld(1), tmpnam(3S), a.out(4), ar(4).
DIAGNOSTICS
``nm: name: cannot open''
if name cannot be read.
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NM(1) (Software Generation System Utilities) NM(1)
``nm: name: bad magic''
if name is not a common object file.
``nm: name: no symbols''
if the symbols have been stripped from name.
Page 4 May 1989