docs: add cpsc command-line man quick reference

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

1 files changed, 74 insertions, 0 deletions

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+% CPSC(1)
+
+# NAME
+
+cpsc - compile and run CIE pseudocode
+
+# SYNOPSIS
+
+**cpsc** [**-r**] [**-o** *output*] *source*
+
+# DESCRIPTION
+
+Compile one pseudocode source file to LLVM IR. Options may appear before or
+after the source path. Source input from stdin is not supported.
+
+Without **-o** or **-r**, replace the source filename's extension with `.ir`
+and save the output beside the source file.
+
+# OPTIONS
+
+**-o** *output*
+:   Save IR to the specified path. May be specified only once. With **-r**,
+    keep this file even if execution fails.
+
+**-r**
+:   Run the compiled program using `lli` from PATH. Without **-o**, use a
+    temporary IR file and delete it afterward, including on execution failure.
+    The program inherits stdin, stdout and stderr; `INPUT` can read terminal
+    or piped input.
+
+# EXAMPLES
+
+Compile and save `test.ir` beside `test.cps`:
+
+```sh
+cpsc test.cps
+```
+
+Choose the output path:
+
+```sh
+cpsc test.cps -o result.ir
+```
+
+Run without saving permanent IR:
+
+```sh
+cpsc test.cps -r
+```
+
+Save IR and run it:
+
+```sh
+cpsc test.cps -r -o result.ir
+```
+
+# EXIT STATUS
+
+**0**
+:   Compilation succeeded. Invoking `cpsc` with no arguments also exits
+    silently with status 0.
+
+**1**
+:   An argument, file, compilation or execution-launch error occurred,
+    including when `lli` cannot be found in PATH.
+
+With **-r**, return `lli`'s exit status. Failure to launch it or a process
+crash returns 1.
+
+# NOTES
+
+Compiler diagnostics go to stderr. Failed compilation does not write IR.
+Successful compilation overwrites an existing output file, but an output path
+that refers to the source file (including a symbolic or hard link) is rejected.