ltrace

 

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 ltrace(1)                                               ltrace(1)
 
 
 
NAME
        ltrace - A library call tracer
 
 
SYNOPSIS
        ltrace  [-dfiLSrtttChV] [-a column] [-s strsize] [-o file­
        name] [-u username]  [-p  pid]  ...  [-e  expr]  [--debug]
        [--demangle] [--align=column] [--output=filename] [--help]
        [--version] [command [arg ...]]
 
 
DESCRIPTION
        ltrace is a program that simply runs the specified command
        until  it  exits.   It  intercepts and records the dynamic
        library calls which are called by the executed process and
        the  signals  which  are received by that process.  It can
        also intercept and print the system calls executed by  the
        program.
 
        Its use is very similar to strace(1).
 
 
OPTIONS
        -d, --debug
               Increase the debugging level.
 
        -f     Trace  child  processes as they are created by cur­
               rently  traced processes as a result of the fork(2)
               or  clone(2)  system  calls.   The  new  process is
               attached as soon as its pid is known.
 
        -i     Print the instruction pointer at the  time  of  the
               library call.
 
        -L     DON'T  display  library  calls  (use it with the -S
               option).
 
        -S     Display system calls as well as library calls
 
        -r     Print a relative timestamp with each  line  of  the
               trace.   This  records  the time difference between
               the beginning of successive lines.
 
        -t     Prefix each line of the trace with the time of day.
 
        -tt    If  given  twice, the time printed will include the
               microseconds.
 
        -ttt   If given thrice, the time printed will include  the
               microseconds   and  the  leading  portion  will  be
               printed as the number of seconds since the epoch.
 
        -C, --demangle
               Decode (demangle) low-level symbol names into user-
               level  names.   Besides removing any initial under­
               score prepended by the system, this makes C++ func­
               tion names readable.
 
        -a, --align column
               Align  return  values  in a secific column (default
               column 50).
 
        -s     Specify the  maximum  string  size  to  print  (the
               default is 32).
 
        -o, --output filename
               Write  the trace output to the file filename rather
               than to stderr.
 
        -u username
               Run command with the userid, groupid and supplemen­
               tary  groups of username.  This option is only use­
               ful when running as root and  enables  the  correct
               execution of setuid and/or setgid binaries.
 
        -p pid Attach  to  the process with the process ID pid and
               begin tracing.
 
        -e expr
               A qualifying expression which modifies which events
               to trace.  The format of the expression is:
               [!]value1[,value2]...
               where the values are the functions to trace.  Using
               an exclamation mark negates the set of values.  For
               example  -e  printf  means to trace only the printf
               library call.  By contrast,  -e  !printf  means  to
               trace every library call except printf.
 
               Note that some shells use the exclamation point for
               history expansion; even  inside  quoted  arguments.
               If so,  escape the exclamation point with a
               backslash.
 
        -h, --help
               Show a summary of the options to ltrace and exit.
 
        -V, --version
               Show the version number of ltrace and exit.
 
 
 BUGS
        It has most of the bugs stated in strace(1).
 
        Manual page and documentation are not very up-to-date.
 
        Option -f sometimes fails to trace some children.
 
        It only works on Linux/i386, Linux/m68k, and Linux/arm
 
        Only ELF32 binaries are supported
 
        If you like to report a bug, send a notice to the  author,
        or  use  the  bug(1)  program  if you are under the Debian
        GNU/Linux distribution.
 
 
FILES
        /etc/ltrace.conf
               System configuration file
 
        ~/.ltrace.conf
               Personal config file, overrides /etc/ltrace.conf
 
 
AUTHOR
        Juan Cespedes <cespedes@debian.org>
 
 
SEE ALSO
        strace(1), ptrace(2)
 
 
 
 
                                                         ltrace(1)

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