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RedHat 9 (Linux i386) - man page for ltrace (redhat section 1)

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ltrace(1)										ltrace(1)

       ltrace - A library call tracer

       ltrace  [-dfiLSrtttChV]	[-a  column] [-s strsize] [-o filename] [-n nr] [-l filename] [-u
       username] [-p pid] ... [-e expr] [--debug] [--demangle]	[--align=column]  [--output=file-
       name] [--indent=nr] [--library=filename] [--help] [--version] [command [arg ...]]

       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).

       -d, --debug
	      Increase the debugging level.  Use more (ie.  =dd ) for greater debugging  informa-

       -f     Trace  child  processes  as  they  are  created by currently  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 dif-
	      ference 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 underscore prepended by the system, this makes C++ function names read-

       -a, --align column
	      Align return values in a secific column (default column is 5/8 of screen width).

       -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.

       -n, --indent nr
	      Indent  trace  output  by  nr number of spaces for each new nested call. Using this
	      option makes the program flow visualization easy to follow.

       -l, --library filename
	      Display only the symbols included in the library filename.  Up to 20 library  names
	      can be specified with several instances of this option.

       -u username
	      Run  command  with  the userid, groupid and supplementary groups of username.  This
	      option is only useful 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:
	      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, you must 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.

       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, Linux/arm, and Linux/S390.

       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.

	      System configuration file

	      Personal config file, overrides /etc/ltrace.conf

       Juan Cespedes <cespedes@debian.org>

       strace(1), ptrace(2)

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