05-21-2008
eval in shell scripting
what is the real usage of eval in shell scripting
whats the difference between
$ cmd
&&
eval cmd
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Hi all,
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my OS is linux
Linux s10-1310 2.6.16.53-0.8.PTF.434477.3.TDC.0-smp #1 SMP Fri Aug 31 06:07:27 PDT 2007 x86_64 x86_64 x86_64 GNU/Linux
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anyone has any info on why this is complaining???
vivek@vivek-c5e55ef2e ~/TAC
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anyone has any info on why this is complaining???
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LEARN ABOUT CENTOS
trace-cmd-start
TRACE-CMD-START(1) TRACE-CMD-START(1)
NAME
trace-cmd-start - start the Ftrace Linux kernel tracer without recording
SYNOPSIS
trace-cmd start [OPTIONS]
DESCRIPTION
The trace-cmd(1) start enables all the Ftrace tracing the same way trace-cmd-record(1) does. The difference is that it does not run threads
to create a trace.dat file. This is useful just to enable Ftrace and you are only interested in the trace after some event has occurred and
the trace is stopped. Then the trace can be read straight from the Ftrace pseudo file system or can be extracted with trace-cmd-extract(1).
OPTIONS
The options are the same as trace-cmd-record(1), except that it does not take options specific to recording (-s, -o, -F, -N, and -t).
SEE ALSO
trace-cmd(1), trace-cmd-record(1), trace-cmd-report(1), trace-cmd-stop(1), trace-cmd-extract(1), trace-cmd-reset(1), trace-cmd-split(1),
trace-cmd-list(1), trace-cmd-listen(1)
AUTHOR
Written by Steven Rostedt, <rostedt@goodmis.org[1]>
RESOURCES
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/trace-cmd.git
COPYING
Copyright (C) 2010 Red Hat, Inc. Free use of this software is granted under the terms of the GNU Public License (GPL).
NOTES
1. rostedt@goodmis.org
mailto:rostedt@goodmis.org
06/11/2014 TRACE-CMD-START(1)