Answers:
这是一个脚本,显示类似于Solaris pstree的输出。不支持任何选项,并且不支持用户匹配。该脚本应可移植到所有POSIX系统。在某些ps
命令与POSIX不兼容的系统上,您可能需要调整传递给的选项ps
。该脚本包括对BSD系统的特定支持,因此应涵盖大多数平台。
#! /bin/sh
## Usage: $0 [PID...]
## Show the processes on the system. For each process, show the process
## id followed by the command line. Show child processes after their parent,
## indented.
## If one or more PIDs are specified, only show the ancestors and
## descendants of those PIDs. If no PID is specified, show the subtree
## rooted at PID 1.
## This utility mimics Solaris pstree(1).
case $(uname) in *BSD*) ps_A='-ax';; *) ps_A='-A';; esac
ps $ps_A -o pid= -o ppid= -o args= |
sort -k 1n |
awk -v targets="$*" '
# children[p]: the " "-separated list of the pids of the children of p
# cmd[p]: command line of p
# list[lb..le]: list of pids yet to traverse
# depth[p]: depth of process p: depth(child) = depth(parent) + 1
# parent[p]: pid of the parent of p
# show[p]: 1 to show p, 2 to show p and all its descendants
BEGIN {
list[0] = 0; lb = 0; le = 0;
depth[0] = -1;
}
{
pid=$1; ppid=$2;
sub(/^ *[0-9]+ +[0-9]+ /, "");
if (pid == ppid) {
# This process is a root: add it to the list of processes to taverse
list[++le] = pid;
} else {
children[ppid] = children[ppid] " " pid;
parent[pid] = ppid;
}
cmd[pid] = $0;
}
END {
# Parse targets into a list of pids (or 1 if none is specified).
split("_" targets, a, /[^0-9]+/);
delete a[1];
if (a[2] == "") a[2] = 1;
for (i in a) {
show[a[i]] = 2; # Show targets recursively
p = parent[a[i]];
# Show target ancestors
while (p && !show[p]) {
show[p] = 1;
p = parent[p];
}
}
# Traverse the list of processes
while (lb <= le) {
pid = list[lb++];
# Add children to the list of processes to traverse
split(children[pid], a);
for (i in a) {
list[--lb] = a[i];
depth[a[i]] = depth[pid] + 1;
if (show[pid] > 1) show[a[i]] = show[pid];
}
# Show the current process if desired, indenting to the right depth
if (show[pid]) {
for (i = 1; i <= depth[pid]; i++) printf(" ");
printf("%-5d ", pid);
print cmd[pid];
}
}
}
'
ps axf
。我发现它更具可读性。