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+% CPSC(1)
+
+# NAME
+
+cpsc - compile and run CIE pseudocode
+
+# SYNOPSIS
+
+**cpsc** [**-r**] [**-o** *output*] *source*
+
+**cpsc** **-h**
+
+# 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
+
+**-h**
+:   Print only the documentation entry point: `man 1 cpsc` on Unix/macOS, or Start Menu > cpsc > cpsc Help on Windows. Return successfully without compiling, even when other arguments are present.
+
+**-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 with the runner selected at build time (see EXECUTION MODES). Without **-o**, do not save permanent IR. The program inherits stdin, stdout and stderr; `INPUT` can read terminal or piped input.
+
+# EXECUTION MODES
+
+The executable has one of the following execution modes, selected when it was built. All modes can compile to LLVM IR; the mode determines whether and how **-r** runs the program.
+
+**PATH**
+:   Run `lli` from PATH. If it cannot be found, **-r** fails before compilation or output writing. Without **-o**, write temporary IR and delete it afterward, including on execution failure.
+
+**EMBEDDED**
+:   Run the statically linked LLVM engine inside `cpsc`, without looking for `lli` in PATH. Without **-o**, execute the module in memory. Users do not need LLVM or `lli` installed; the executable may still depend on the operating system's C runtime libraries.
+
+**NONE**
+:   Reject **-r** with an error before compilation or output writing. Compilation to IR remains available.
+
+# 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, or **-h** printed the documentation entry point.
+
+**1**
+:   An argument, file, compilation or execution-engine error occurred, including missing input, when PATH mode cannot find `lli` or NONE mode receives **-r**.
+
+With **-r**, return the executed program's exit status. In PATH mode, failure to launch `lli` or a child-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.
+
+Missing input, including invoking `cpsc` without arguments, reports `cpsc: fatal error: no input files`. Ordinary lexical, syntax and semantic errors use `error:`; failures that prevent compilation, such as file I/O errors, use `fatal error:`. Compilation and argument failures end with one `compilation terminated.` line. Execution-stage failures do not print that line.
+
+# SEE ALSO
+
+[cpsc-language-overview(7)](language/cpsc-language-overview.7.md) describes supported syntax and links to the keyword and built-in function manuals.