@@ -72,34 +72,34 @@ func hasCNBLauncherEntrypoint(ic ImageConfiguration) bool {
7272// execution environment as configured by the various buildpacks, and then hands off to the
7373// configured launch. The CNB launcher supports three types of launches:
7474//
75- // 1. _predefined processes_ are named sets of command+arguments (similar to a container image's
76- // ENTRYPOINT/CMD). Processes are created by the buildpacks, and oftentimes there is a
77- // buildpack that parses a user's `Procfile` and turns those contents into processes.
78- // There are two types of process definitions:
79- // - *direct*: these are passed uninterpreted to os.exec; the command is resolved in PATH
80- // Note that in practice we see direct-style definitions that execute `/bin/sh -c ...`
81- // - *script*: the command is treated as a shell script and passed to `sh -c`, and any remaining
82- // arguments on the container command-line are added to the shell and so become available
83- // as positional arguments (see https://github.com/buildpacks/lifecycle/issues/218#issuecomment-567091462).
84- // For example: `sh -c 'echo $0 $1 $2 $3' arg0 arg1 arg2 arg3` => `arg0 arg1 arg2 arg3`.
85- // 2. _direct execs_: the user can provide a command-line which is treated like a _direct process_.
86- // 3. _shell scripts_: the user can provide a shell script as the first argument and any
87- // remaining arguments are available as positional arguments like _script processes_.
75+ // 1. _predefined processes_ are named sets of command+arguments (similar to a container image's
76+ // ENTRYPOINT/CMD). Processes are created by the buildpacks, and oftentimes there is a
77+ // buildpack that parses a user's `Procfile` and turns those contents into processes.
78+ // There are two types of process definitions:
79+ // - *direct*: these are passed uninterpreted to os.exec; the command is resolved in PATH
80+ // Note that in practice we see direct-style definitions that execute `/bin/sh -c ...`
81+ // - *script*: the command is treated as a shell script and passed to `sh -c`, and any remaining
82+ // arguments on the container command-line are added to the shell and so become available
83+ // as positional arguments (see https://github.com/buildpacks/lifecycle/issues/218#issuecomment-567091462).
84+ // For example: `sh -c 'echo $0 $1 $2 $3' arg0 arg1 arg2 arg3` => `arg0 arg1 arg2 arg3`.
85+ // 2. _direct execs_: the user can provide a command-line which is treated like a _direct process_.
86+ // 3. _shell scripts_: the user can provide a shell script as the first argument and any
87+ // remaining arguments are available as positional arguments like _script processes_.
8888//
8989// Script-style launches support referencing environment variables since they are expanded by the shell.
9090//
9191// Configuring the launch depends on the CNB Platform API version being used, which is determined by
9292// the builder's lifecycle version, which is itself determined by the pack used to create a builder.
9393// - In Platform API 0.3 (pack 0.12 and earlier / lifecycle 0.8 and earlier) the image entrypoint
9494// is set to `/cnb/lifecycle/launcher`. The launch is determined by:
95- // 1. If there are arguments:
96- // 1. If there is a single argument and it matches a process type, then the corresponding
97- // process is launched.
98- // 2. If the first argument is `--` then the remaining arguments are treated as a _direct exec_.
99- // 3. Otherwise the first argument is treated as a shell script launch with the first
100- // argument as the script and remaining arguments are positional arguments to the script.
101- // 2. If there are no arguments, a process type is taken from the `CNB_PROCESS_TYPE`
102- // environment variable, defaulting to `web`.
95+ // 1. If there are arguments:
96+ // 1. If there is a single argument and it matches a process type, then the corresponding
97+ // process is launched.
98+ // 2. If the first argument is `--` then the remaining arguments are treated as a _direct exec_.
99+ // 3. Otherwise the first argument is treated as a shell script launch with the first
100+ // argument as the script and remaining arguments are positional arguments to the script.
101+ // 2. If there are no arguments, a process type is taken from the `CNB_PROCESS_TYPE`
102+ // environment variable, defaulting to `web`.
103103// - In Platform API 0.4 (pack 0.13 / lifecycle 0.9) the process types are turned into executables
104104// found in `/cnb/process/`, and the image entrypoint is set to the corresponding executable for
105105// the default process type. `CNB_PROCESS_TYPE` is ignored in this situation. A different process
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