Okay I think this might be a very special case with the SCons script invocation.
The main python script / SCons probably internally creates a new process for each invocation of a user’s extra_script. And there’s some mechanism to read from that process’s output and display it back in the main processes’s output. But that thing is also buffered or reads line-wise. A simple test like
import sys
Import("env")
print("Normal output")
print("No newline at end but flushed", end="")
sys.stdout.flush()
env.Exit(-1)
as an extra_scripts script reveals output
Dependency Graph
|-- <ESP8266WiFi> 1.0 (C:\Users\Max\.platformio\packages\framework-arduinoespressif8266\libraries\ESP8266WiFi)
Building in release mode
Normal output
======================== [FAILED] Took 0.99 seconds ========================
so the second output is not displayed although we flush the output of our process. If one would execute that as a normal python script (with env stuff removed)
>python test.py
Normal output
No newline at end but flushed
it does output.
@ivankravets do you know about these special cases when an extra_script does print something but without a newline (but still flushes) why it wouldn’t output something in the terminal?
The special usecase here is that e.g. pio run -t specialgdb would launch the user, in the terminal, in a GDB session, but when using code like
import os
import re
import sys
import time
import subprocess
Import("env")
#print(env.Dump())
gdb_path = ""
# Find the current platform compiler by searching the $PATH
# which will be in a platformio toolchain bin folder
path_regex = re.escape(env['PROJECT_PACKAGES_DIR'])
gcc = "gdb"
if env['PLATFORM'] == 'win32':
path_separator = ';'
path_regex += r'.*\\bin'
gcc += ".exe"
else:
path_separator = ':'
path_regex += r'/.+/bin'
# Search for the compiler
print("PATH: " + str(env['ENV']['PATH'].split(path_separator)))
for pathdir in env['ENV']['PATH'].split(path_separator):
if not re.search(path_regex, pathdir, re.IGNORECASE):
continue
for filepath in os.listdir(pathdir):
if not filepath.endswith(gcc):
continue
# Use entire path to not rely on env PATH
filepath = os.path.sep.join([pathdir, filepath])
print("Compiler found: " + str(filepath))
gdb_path = str(filepath)
def command_gdb(*args, **kwargs):
print("Entrypoint")
# attempt to set output to unbuffered - unsuccessfull though
os.environ["PYTHONUNBUFFERED"] = "1"
print("GDB path = " + gdb_path)
# does not work: input is not echoed, "(gdb)" prompt does not appear
os.system(gdb_path)
#os.execl(gdb_path, "--help")
# workaround.
# for windows: "start" <command> opens .exe directly wihch opens a cmd "GUI" window.
# for linux we probably want to open a new GUI shell or something?
# process output is not displayed inline..
#subprocess.Popen(["start", gdb_path], bufsize=0, shell=True, start_new_session=True, stdout=sys.stdout, stdin=sys.stdin).wait()
env.AddCustomTarget(
name="specialgdb",
dependencies=None,
actions=[
command_gdb
],
title="Launch special GDB",
description="Launch special GDB"
)
the output is
command_gdb(["specialgdb"], [])
Entrypoint
GDB path = C:\Users\Max\.platformio\packages\toolchain-xtensa\bin\xtensa-lx106-elf-gdb.exe
GNU gdb (GDB) 8.2.50.20180723-git
Copyright (C) 2018 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.
Type "show copying" and "show warranty" for details.
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Type "show configuration" for configuration details.
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<http://www.gnu.org/software/gdb/bugs/>.
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when the final lines should have been, when just invoking the program
Also output is not echoed which is a mystery to me.
@csetera there’s also a workaround at the bottom of that code that you might want to look at.
One can also do other fancy workarounds. Like e.g., let the Python script write a .bat file that has the correct invocation line and then wrap it like pio run -t specialgdb && run_gdb.bat in one command
Any idea why 