我有一个使用SCons组合在一起的项目的简单构建系统。该项目有相当多的源文件，我认为在构建进行时显示某种进度信息会是用户友好的。SCons 提供了构建变量CXXCOMSTR，我可以覆盖这些变量来控制在每个构建步骤中显示到终端的内容。例如，而不是看到类似的东西：
gcc file.c -o file.o
有类似的东西会很好：
[1/10] Compiling file.c: `gcc file.c -o file.o`
其中[1/10]指定这是在此构建期间更新的十个目标中的第一个。有什么方法可以访问这些信息，以便我可以生成这样的消息？似乎我需要知道正在更新的目标的总数（这是基于 SCons 所做的依赖扫描）以及枚举每个目标的某种方式。我知道类似的行为与 CMake 和 waf 等其他构建系统相似，但在 SCons 的（扩展的）文档中没有遇到任何内容。
这可以通过Progress() SCons 函数来完成。
SCons 手册页中有更多示例，只需搜索“Progress”即可。
您可以提供要调用的函数、将定期显示的字符串或将以旋转方式显示的字符串列表。您可以访问正在构建的当前目标，但我认为不可能知道完成百分比。
我能够想出一个相当不错的解决方法，允许您以百分比显示构建进度。基本上以下代码的工作原理是这样的：
[??%]在每个目标旁边 .scons_progress[50%]）。[??%]并更新.scons_progress interval为 5，以便它仅每 5 个节点更新一次缓存这是代码：
custom_utils.py在下site_scons/：_
PROGRESS = {
"env": None,
"nodes": 0,
"interval": 1,
"total": 0,
"cache": {},
"cache_key": "_",
"cache_name": ".scons_progress",
"cache_update": False
}
def get_progress_total():
return PROGRESS["cache"].get(PROGRESS["cache_key"], 0)
def update_progress_cache():
PROGRESS["cache"][PROGRESS["cache_key"]] = PROGRESS["nodes"]
with open(PROGRESS["cache_name"], "w") as f:
f.write(json.dumps(PROGRESS["cache"]))
def load_progress_cache():
try:
with open(PROGRESS["cache_name"]) as f:
PROGRESS["cache"] = json.load(f)
cache_key = "_".join(COMMAND_LINE_TARGETS)
if cache_key:
PROGRESS["cache_key"] = cache_key
except IOError as e:
pass
def progress_function(node):
PROGRESS["nodes"] += PROGRESS["interval"]
#Only update cached environment if it is not None
if node.env:
PROGRESS["env"] = node.env
PROGRESS["env"].Replace(PROGRESS = "[??%]")
#Update display message
if PROGRESS["nodes"] <= PROGRESS["total"]:
PROGRESS["env"].Replace(PROGRESS = "[%d%%]" % (100*PROGRESS["nodes"]/PROGRESS["total"]))
#If current node is more than total, we need to update the cache
elif not PROGRESS["cache_update"]:
PROGRESS["cache_update"] = True
PROGRESS["env"].Replace(PROGRESS = "[??%]")
#If cache flag is on, update cache file
else:
update_progress_cache()
def progress_settings(env, interval):
load_progress_cache()
PROGRESS["interval"] = interval
PROGRESS["env"] = env
PROGRESS["total"] = get_progress_total()
Progress(progress_function, interval=PROGRESS["interval"])
在SConstruct：
if GetOption("progress"):
custom_utils.progress_settings(env, 5)
样本输出：
user@linuxbox:~/project1$ scons -j4 --progress
scons: Reading SConscript files ...
scons: done reading SConscript files.
scons: Building targets ...
[??%] Compiling (shared): src/ExpressRuntimeException.os
[??%] Compiling (shared): src/Application.os
[??%] Compiling (shared): src/Callback.os
[??%] Compiling (shared): src/Response.os
[??%] Compiling (shared): src/Router.os
[??%] Compiling (shared): src/Route.os
[??%] Compiling (shared): src/Regex.os
[??%] Compiling (shared): src/tools.os
[??%] Linking (shared): libexpresscpp.so
scons: done building targets.
user@linuxbox:~/project1$ scons -c
scons: Reading SConscript files ...
scons: done reading SConscript files.
scons: Cleaning targets ...
Removed src/ExpressRuntimeException.os
Removed src/Application.os
Removed src/Callback.os
Removed src/Response.os
Removed src/Router.os
Removed src/Route.os
Removed src/Regex.os
Removed src/tools.os
Removed libexpresscpp.so
scons: done cleaning targets.
user@linuxbox:~/project1$ scons -j4 --progress
scons: Reading SConscript files ...
scons: done reading SConscript files.
scons: Building targets ...
[14%] Compiling (shared): src/ExpressRuntimeException.os
[51%] Compiling (shared): src/Application.os
[59%] Compiling (shared): src/Callback.os
[66%] Compiling (shared): src/Response.os
[74%] Compiling (shared): src/Router.os
[81%] Compiling (shared): src/Route.os
[88%] Compiling (shared): src/Regex.os
[96%] Compiling (shared): src/tools.os
[100%] Linking (shared): libexpresscpp.so
scons: done building targets.
我非常喜欢 RPGilespie 的回答，并在我们拥有约 4500 个节点的软件包中使用它。不过，我做了一些调整，并认为我会发布它以防万一它对任何人有帮助。主要区别在于：
1.) 我添加了一个在作业结束时运行的命令，以根据这篇文章将总节点数写入文件。这样就不必在进度功能中不断地访问文件系统。
2.) 由于 1.) 每次运行 scons 时它都会更新文件（不仅仅是当它检测到节点数超过之前的最大值时）。如果您正在处理树的单个部分（即较少的节点）并且不断重建该部分，这将很有用。
3.）我让它在屏幕更新之前放回车，这样它就可以直接从progress_function写入它，而不是为以后设置一个变量。这有一个额外的好处，即在开始扫描主要构建的树时显示计数器更新。
作为旁注，我在这里将更新间隔设置为 1。原因是因为我注意到有时与单个构建命令关联的节点数少于导致它不打印该行的计数器的时间间隔。通过上述对计数器文件编写方式的更改，我没有看到任何明显的减速。YMMV。
我将以下内容放在我的 SConstruct 文件的末尾：
screen = open('/dev/tty', 'w')
node_count = 0
node_count_max = 0
node_count_interval = 1
node_count_fname = str(env.Dir('#')) + '/.scons_node_count'
def progress_function(node):
global node_count, node_count_max, node_count_interval, node_count_fname
node_count += node_count_interval
if node_count > node_count_max: node_count_max = 0
if node_count_max>0 :
screen.write('\r[%3d%%] ' % (node_count*100/node_count_max))
screen.flush()
def progress_finish(target, source, env):
global node_count
with open(node_count_fname, 'w') as f: f.write('%d\n' % node_count)
try:
with open(node_count_fname) as f: node_count_max = int(f.readline())
except: pass
Progress(progress_function, interval=node_count_interval)
progress_finish_command = Command('progress_finish', [], progress_finish)
Depends(progress_finish_command, BUILD_TARGETS)
if 'progress_finish' not in BUILD_TARGETS:
BUILD_TARGETS.append('progress_finish')
示例输出是：
[ 0%] Installing [/Users/davidl/HallD/builds/sim-recon/Darwin_macosx10.11-x86_64-llvm8.0.0/bin/MakeEventWriterROOT.pl]
[ 0%] Installing [/Users/davidl/HallD/builds/sim-recon/Darwin_macosx10.11-x86_64-llvm8.0.0/bin/MakeReactionPlugin.pl]
[ 0%] Compiling [programs/Simulation/genr8/genkin.c]
[ 0%] Compiling [programs/Simulation/genr8/genr8.c]
[ 3%] Compiling [programs/Utilities/hddm/hddm-cpp.cpp]
[ 3%] Compiling [programs/Utilities/hddm/XString.cpp]
[ 3%] Compiling [programs/Utilities/hddm/XParsers.cpp]
[ 3%] Compiling [programs/Utilities/hddm/md5.c]
[ 4%] Compiling [external/xstream/src/base64.cpp]
[ 4%] Compiling [external/xstream/src/bz.cpp]
[ 4%] Compiling [external/xstream/src/common.cpp]
[ 4%] Compiling [external/xstream/src/dater.cpp]
[ 4%] Linking [.Darwin_macosx10.11-x86_64-llvm8.0.0/programs/Simulation/genr8/genr8]
[ 4%] Installing [/Users/davidl/HallD/builds/sim-recon/Darwin_macosx10.11-x86_64-llvm8.0.0/bin/genr8]
[ 4%] Compiling [external/xstream/src/debug.cpp]
[ 4%] Compiling [external/xstream/src/digest.cpp]
...
为了完整起见，这是我的 COMSTR 定义：
env.Replace( CCCOMSTR = "Compiling [$SOURCE]",
CXXCOMSTR = "Compiling [$SOURCE]",
FORTRANPPCOMSTR = "Compiling [$SOURCE]",
FORTRANCOMSTR = "Compiling [$SOURCE]",
SHCCCOMSTR = "Compiling [$SOURCE]",
SHCXXCOMSTR = "Compiling [$SOURCE]",
LINKCOMSTR = "Linking [$TARGET]",
SHLINKCOMSTR = "Linking [$TARGET]",
INSTALLSTR = "Installing [$TARGET]",
ARCOMSTR = "Archiving [$TARGET]",
RANLIBCOMSTR = "Ranlib [$TARGET]")