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GNU Make's bug (exec a directory)
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#!/bin/sh | |
set -x | |
# Create a folder named 'docker'. The folder would have 'executible' flag set | |
mkdir -p `pwd`/scripts/docker | |
# Add the script to the path BEFORE the rest | |
export PATH=`pwd`/scripts:$PATH | |
# Create a simple Makefile to run a docker command | |
cat<<EOF > Makefile | |
all: | |
docker ps | |
EOF | |
# Run the make command | |
make | |
# The output would be | |
# docker ps | |
# make: docker: Permission denied | |
# `strace` would reveal the mystery (with some sed magic to strip the private stuff) | |
strace -f -e execve make 2>&1 | sed "s|/home/$(whoami)/.*/scripts/docker|/path/to/scripts/docker|g" | |
# The output would be like: | |
# | |
# execve("/usr/bin/make", ["make"], 0x7ffd59f59e68 /* 72 vars */) = 0 | |
# docker ps | |
# strace: Process 2833630 attached | |
# [pid 2833630] execve("/path/to/scripts/docker", ["docker", "ps"], 0x55884ea326f0 /* 75 vars */) = -1 EACCES (Permission denied) | |
# [pid 2833630] +++ exited with 127 +++ | |
# make: docker: Permission denied | |
# make: *** [Makefile:2: all] Error 127 | |
# Looks like make does not care if a command is a directory, but just checks for 'x' flag. | |
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