pstack strace,pstack命令

虚拟的流沙，使用pstack查看系统进程的堆栈时需要sudo。虚拟的流沙第一行使用的bash，不可用dash。------------------------------------#!/bin/bash if test $# -ne 1; then
    echo "Usage: `basename $0 .sh` <process-id>" 1>&2
    exit 1
fi if test ! -r /proc/$1; then
    echo "Process $1 not found." 1>&2
    exit 1
fi # GDB doesn't allow "thread apply all bt" when the process isn't
# threaded; need to peek at the process to determine if that or the
# simpler "bt" should be used. backtrace="bt"
if test -d /proc/$1/task ; then
    # Newer kernel; has a task/ directory.
    if test `/bin/ls /proc/$1/task | /usr/bin/wc -l` -gt 1 2>/dev/null ; then
        backtrace="thread apply all bt"
    fi
elif test -f /proc/$1/maps ; then
    # Older kernel; go by it loading libpthread.
    if /bin/grep -e libpthread /proc/$1/maps > /dev/null 2>&1 ; then
        backtrace="thread apply all bt"
    fi
fi GDB=${GDB:-/usr/bin/gdb} if $GDB -nx --quiet --batch --readnever > /dev/null 2>&1; then
    readnever=--readnever
else
    readnever=
fi # Run GDB, strip out unwanted noise.
$GDB --quiet $readnever -nx /proc/$1/exe $1 <<EOF 2>&1 |
$backtrace
EOF
/bin/sed -n
    -e 's/^(gdb) //'
    -e '/^#/p'
    -e '/^Thread/p'