<html><head></head><body><div style="font-family: Verdana;font-size: 12.0px;"><div><span style="color: rgb(34, 34, 34); font-family: arial, sans-serif; font-size: 12.8000001907349px; line-height: normal;">Hello!</span>
<div style="color: rgb(34, 34, 34); font-family: arial, sans-serif; font-size: 12.8000001907349px; line-height: normal;"> </div>
<div style="color: rgb(34, 34, 34); font-family: arial, sans-serif; font-size: 12.8000001907349px; line-height: normal;">strace requires that the ptrace_scope is set to 0 in order to be able to attach to non child processes.</div>
<div style="color: rgb(34, 34, 34); font-family: arial, sans-serif; font-size: 12.8000001907349px; line-height: normal;">If attaching fails strace prints an error message, but the exit code is 0. I expect a nonzero exit code.</div>
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<div style="color: rgb(34, 34, 34); font-family: arial, sans-serif; font-size: 12.8000001907349px; line-height: normal;">
<div>The manual states the following:</div>
<div> </div>
<div>> When using -p, the exit status of strace is zero unless there was an unexpected error in doing the tracing.</div>
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<div style="color: rgb(34, 34, 34); font-family: arial, sans-serif; font-size: 12.8000001907349px; line-height: normal;"> </div>
<div style="color: rgb(34, 34, 34); font-family: arial, sans-serif; font-size: 12.8000001907349px; line-height: normal;">The behavior is reproducable with strace 4.8 and 4.10.</div>
<div style="color: rgb(34, 34, 34); font-family: arial, sans-serif; font-size: 12.8000001907349px; line-height: normal;"> </div>
<div style="color: rgb(34, 34, 34); font-family: arial, sans-serif; font-size: 12.8000001907349px; line-height: normal;">An example:</div>
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<div>$ strace -p 1234</div>
<div>strace: attach: ptrace(PTRACE_ATTACH, ...): Operation not permitted</div>
<div>Could not attach to process. If your uid matches the uid of the target</div>
<div>process, check the setting of /proc/sys/kernel/yama/ptrace_<wbr/>scope, or try</div>
<div>again as the root user. For more details, see /etc/sysctl.d/10-ptrace.conf</div>
<div>$ echo $?</div>
<div>> 0</div>
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<div style="color: rgb(34, 34, 34); font-family: arial, sans-serif; font-size: 12.8000001907349px; line-height: normal;"> </div>
<div style="color: rgb(34, 34, 34); font-family: arial, sans-serif; font-size: 12.8000001907349px; line-height: normal;">Regards,</div>
<div style="color: rgb(34, 34, 34); font-family: arial, sans-serif; font-size: 12.8000001907349px; line-height: normal;">Oliver Hanappi</div>
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