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- What does $$ mean in the shell? 11 answers
- $$在shell中意味着什么？ 11个答案
I came across "$$" expression in shell script, something like this
我在shell脚本中遇到了“$$”表达式，就像这样
TFILE=$$
TFILE = $$
Can anyone tell me its meaning?
谁能告诉我它的含义？
4 个解决方案
#1
20
$$ means the process ID of the currently-running process.
$$表示当前正在运行的进程的进程ID。
#2
5
It's the process id of the current process - see a previous question on * for details: What does $$ mean in the shell?
它是当前进程的进程ID - 有关详细信息，请参阅*上的上一个问题：$$在shell中的含义是什么？
#3
1
$$ is the process id of the currently running process in UNIX.
$$是UNIX中当前正在运行的进程的进程ID。
mostly it is used with naming of logfiles aor temp files, such that there is no conflict of file names while multiple instances of the same scripts are running.
主要用于命名日志文件或临时文件，以便在运行相同脚本的多个实例时不会发生文件名冲突。
#4
0
echo "$$" prints PID of current running process.
echo“$$”打印当前运行进程的PID。
#1
20
$$ means the process ID of the currently-running process.
$$表示当前正在运行的进程的进程ID。
#2
5
It's the process id of the current process - see a previous question on * for details: What does $$ mean in the shell?
它是当前进程的进程ID - 有关详细信息，请参阅*上的上一个问题：$$在shell中的含义是什么？
#3
1
$$ is the process id of the currently running process in UNIX.
$$是UNIX中当前正在运行的进程的进程ID。
mostly it is used with naming of logfiles aor temp files, such that there is no conflict of file names while multiple instances of the same scripts are running.
主要用于命名日志文件或临时文件，以便在运行相同脚本的多个实例时不会发生文件名冲突。
#4
0
echo "$$" prints PID of current running process.
echo“$$”打印当前运行进程的PID。