NM(1P) - phpMan

NM(1P)                     POSIX Programmer's Manual                    NM(1P)

PROLOG
       This  manual  page is part of the POSIX Programmer's Manual.  The Linux
       implementation of this interface may differ (consult the  corresponding
       Linux  manual page for details of Linux behavior), or the interface may
       not be implemented on Linux.
NAME
       nm - write the name list of an object file (DEVELOPMENT)
SYNOPSIS
       nm [-APv][-efox][ -g| -u][-t format] file...
DESCRIPTION
       This utility shall be provided on systems that support  both  the  User
       Portability  Utilities  option  and  the Software Development Utilities
       option. On other systems it  is  optional.  Certain  options  are  only
       available on XSI-conformant systems.
       The  nm  utility  shall  display  symbolic information appearing in the
       object file, executable file, or object-file library named by file.  If
       no  symbolic  information  is  available for a valid input file, the nm
       utility shall report that fact, but not consider it an error condition.
       The default base used when numeric values are written  is  unspecified.
        On XSI-conformant systems, it shall be decimal.
OPTIONS
       The  nm  utility  shall  conform  to  the  Base  Definitions  volume of
       IEEE Std 1003.1-2001, Section 12.2, Utility Syntax Guidelines.
       The following options shall be supported:
       -A     Write the full pathname or library name of  an  object  on  each
              line.
       -e     Write only external (global) and static symbol information.
       -f     Produce full output. Write redundant symbols ( .text, .data, and
              .bss), normally suppressed.
       -g     Write only external (global) symbol information.
       -o     Write numeric values in octal (equivalent to -t o).
       -P     Write information in a portable output format, as  specified  in
              the STDOUT section.
       -t  format
              Write  each  numeric  value  in the specified format. The format
              shall be 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.

       -u     Write only undefined symbols.
       -v     Sort output by value instead of alphabetically.
       -x     Write numeric values in hexadecimal (equivalent to -t x).

OPERANDS
       The following operand shall be supported:
       file   A  pathname  of  an object file, executable file, or object-file
              library.

STDIN
       See the INPUT FILES section.
INPUT FILES
       The input file shall be an object file, an  object-file  library  whose
       format  is  the same as those produced by the ar utility for link edit-
       ing, or an executable file. The nm utility may accept additional imple-
       mentation-defined object library formats for the input file.
ENVIRONMENT VARIABLES
       The following environment variables shall affect the execution of nm:
       LANG   Provide  a  default value for the internationalization variables
              that are unset or null. (See  the  Base  Definitions  volume  of
              IEEE Std 1003.1-2001,  Section  8.2,  Internationalization Vari-
              ables for the precedence of internationalization variables  used
              to determine the values of locale categories.)
       LC_ALL If  set  to a non-empty string value, override the values of all
              the other internationalization variables.
       LC_COLLATE
              Determine the locale for character collation information for the
              symbol-name and symbol-value collation sequences.
       LC_CTYPE
              Determine  the  locale  for  the  interpretation of sequences of
              bytes of text data as characters (for  example,  single-byte  as
              opposed to multi-byte characters in arguments).
       LC_MESSAGES
              Determine  the  locale  that should be used to affect the format
              and contents of diagnostic messages written to standard error.
       NLSPATH
              Determine the location of message catalogs for the processing of
              LC_MESSAGES .

ASYNCHRONOUS EVENTS
       Default.
STDOUT
       If  symbolic  information  is present in the input files, then for each
       file or for each member of an archive, the nm utility shall  write  the
       following  information  to  standard output.  By default, the format is
       unspecified, but the output shall be sorted  alphabetically  by  symbol
       name:
        * Library or object name, if -A is specified
        * Symbol name
        * Symbol type, which shall either be one of the following single char-
          acters or an implementation-defined type  represented  by  a  single
          character:
       A
              Global absolute symbol.
       a
              Local absolute symbol.
       B
              Global "bss" (that is, uninitialized data space) symbol.
       b
              Local bss symbol.
       D
              Global data symbol.
       d
              Local data symbol.
       T
              Global text symbol.
       t
              Local text symbol.
       U
              Undefined symbol.

        * Value of the symbol
        * The size associated with the symbol, if applicable
       This information may be supplemented by additional information specific
       to the implementation.
       If the -P option is specified, the previous information shall  be  dis-
       played  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> shall be formatted as follows:
        * If -A is not specified,  <library/object name>  shall  be  an  empty
          string.
        * If  -A is specified and the corresponding file operand does not name
          a library:

          "%s: ", <file>
        * If -A is specified  and  the  corresponding  file  operand  names  a
          library.  In  this case, <object file> shall name 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
       shall write a line identifying the object containing the following sym-
       bols before the lines containing those symbols, in the form:
        * If the corresponding file operand does not name a library:

          "%s:\n", <file>
        * If  the  corresponding  file  operand names a library; in this case,
          <object file> shall be the name of the file in the library  contain-
          ing the following symbols:

          "%s[%s]:\n", <file>, <object file>
       If  -P  is specified, but -t is not, the format shall be as if -t x had
       been specified.
STDERR
       The standard error shall be used only for diagnostic messages.
OUTPUT FILES
       None.
EXTENDED DESCRIPTION
       None.
EXIT STATUS
       The following exit values shall be returned:
        0     Successful completion.
       >0     An error occurred.

CONSEQUENCES OF ERRORS
       Default.
       The following sections are informative.
APPLICATION USAGE
       Mechanisms for dynamic linking make this utility less  meaningful  when
       applied  to  an executable file because a dynamically linked executable
       may omit numerous library routines that would be found in a  statically
       linked executable.
EXAMPLES
       None.
RATIONALE
       Historical  implementations of nm have used different bases for numeric
       output and supplied  different  default  types  of  symbols  that  were
       reported. The -t format option, similar to that used in od and strings,
       can be used to specify the numeric base; -g  and  -u  can  be  used  to
       restrict  the  amount of output or the types of symbols included in the
       output.
       The compromise of using -t format versus using -d, -o, and other  simi-
       lar  options  was necessary because of differences in the meaning of -o
       between implementations. The -o option from BSD has been provided  here
       as -A to avoid confusion with the -o from System V (which has been pro-
       vided here as -t and as -o on XSI-conformant systems).
       The option list was significantly reduced from that provided by histor-
       ical implementations.
       The  nm  description is a subset of both the System V and BSD nm utili-
       ties with no specified default output.
       It was recognized that mechanisms for dynamic linking make this utility
       less  meaningful  when applied to an executable file (because a dynami-
       cally linked executable file may omit numerous  library  routines  that
       would  be  found in a statically linked executable file), but the value
       of nm during software development was judged to outweigh other  limita-
       tions.
       The default output format of nm is not specified because of differences
       in historical implementations. The -P option was added  to  allow  some
       type  of  portable  output  format. After a comparison of the different
       formats used in SunOS, BSD, SVR3, and SVR4, it was  decided  to  create
       one that did not match the current format of any of these four systems.
       The format devised is easy to parse by humans, easy to parse  in  shell
       scripts, and does not need to vary depending on locale (because no Eng-
       lish descriptions are included). All of the systems currently have  the
       information available to use this format.
       The format given in nm STDOUT uses spaces between the fields, which may
       be any number of <blank>s required to align the  columns.  The  single-
       character  types  were  selected  to match historical practice, and the
       requirement that implementation additions  also  be  single  characters
       made parsing the information easier for shell scripts.
FUTURE DIRECTIONS
       None.
SEE ALSO
       ar, c99
COPYRIGHT
       Portions  of  this text are reprinted and reproduced in electronic form
       from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology
       --  Portable  Operating  System  Interface (POSIX), The Open Group Base
       Specifications Issue 6, Copyright (C) 2001-2003  by  the  Institute  of
       Electrical  and  Electronics  Engineers, Inc and The Open Group. In the
       event of any discrepancy between this version and the original IEEE and
       The  Open Group Standard, the original IEEE and The Open Group Standard
       is the referee document. The original Standard can be  obtained  online
       at http://www.opengroup.org/unix/online.html .

IEEE/The Open Group                  2003                               NM(1P)