add man page gosh(1) and include it in the deb/rpm packages

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

.gitignore

@@ -1,2 +1,3 @@
 gosh
 dist/
+packaging/man/gosh.1.gz

.goreleaser.yaml

@@ -12,6 +12,8 @@ before:
   hooks:
     - go mod tidy
     - go test ./...
+    # Man page with the release version, gzipped for /usr/share/man
+    - sh -c 'sed "s/@VERSION@/{{ .Version }}/" packaging/man/gosh.1 | gzip -9n > packaging/man/gosh.1.gz'
 
 builds:
   - id: gosh
@@ -50,6 +52,10 @@ archives:
       - src: README.md
         info:
           mode: 0644
+      - src: packaging/man/gosh.1.gz
+        dst: man/gosh.1.gz
+        info:
+          mode: 0644
 
 nfpms:
   - id: gosh
@@ -75,6 +81,10 @@ nfpms:
         dst: /usr/share/doc/gosh/README.md
         file_info:
           mode: 0644
+      - src: packaging/man/gosh.1.gz
+        dst: /usr/share/man/man1/gosh.1.gz
+        file_info:
+          mode: 0644
     scripts:
       postinstall: packaging/scripts/postinstall.sh
       postremove: packaging/scripts/postremove.sh

README.md

@@ -507,4 +507,4 @@ git push origin v0.1.0
 goreleaser release --clean
 ```
 
-Das Paket installiert `/usr/bin/gosh` und trägt die Shell in `/etc/shells` ein, sodass sie mit `chsh -s /usr/bin/gosh` gesetzt werden kann.
+Das Paket installiert `/usr/bin/gosh` und die Man-Page `gosh(1)` (`man gosh`, Quelle: `packaging/man/gosh.1`, lokal ansehen mit `man ./packaging/man/gosh.1`) und trägt die Shell in `/etc/shells` ein, sodass sie mit `chsh -s /usr/bin/gosh` gesetzt werden kann.

packaging/man/gosh.1

@@ -0,0 +1,504 @@
+.\" Man page for gosh. View with: man ./packaging/man/gosh.1
+.\" @VERSION@ is replaced by the release version when building packages.
+.TH GOSH 1 "October 2026" "gosh @VERSION@" "User Commands"
+.SH NAME
+gosh \- a simple shell written in Go
+.SH SYNOPSIS
+.B gosh
+.RB [ \-l ]
+.RB [ \-i ]
+.RB [ \-\-norc ]
+.RB [ \-\-noprofile ]
+.RI [ script ]
+.br
+.B gosh
+.RB [ \-l ]
+.RB [ \-\-noprofile ]
+.B \-c
+.I command
+.br
+.B gosh
+.B \-version
+.SH DESCRIPTION
+.B gosh
+is a small command interpreter with a syntax close to
+.BR sh (1).
+It supports command history, tab completion, variables, command
+substitution, command lists, control structures, pipes, redirections,
+wildcards, brace expansion, aliases and job control.
+.PP
+Without arguments and with a terminal on standard input,
+.B gosh
+starts an interactive shell. With a
+.I script
+argument it runs the commands of that file, with
+.B \-c
+the given command string, and otherwise it reads commands from standard
+input.
+.PP
+.B gosh
+is a proof of concept and not meant for production use.
+.SH OPTIONS
+.TP
+.B \-c \fIcommand\fP
+Run
+.I command
+and exit.
+.TP
+.B \-i
+Force interactive mode, even if standard input is not a terminal.
+.TP
+.BR \-l ", " \-\-login
+Act as a login shell and read the profile files (see
+.BR "STARTUP FILES" ).
+A shell whose
+.I argv[0]
+starts with
+.B \-
+(as started by
+.BR login (1),
+.BR sshd (8)
+or
+.BR "su \-" )
+is a login shell as well.
+.TP
+.B \-\-norc
+Do not read the goshrc files.
+.TP
+.B \-\-noprofile
+Do not read the profile files.
+.TP
+.BR \-version ", " \-\-version ", " \-V
+Print the version, branch and commit and exit.
+.TP
+.BR \-h ", " \-\-help
+Print a usage summary and exit.
+.TP
+.B \-
+Read commands from standard input.
+.SH NON-INTERACTIVE USE
+Scripts, command strings and commands read from a pipe are executed line
+by line. Empty lines and lines starting with
+.B #
+are skipped, so a script may start with
+.BR "#!/usr/bin/gosh" .
+A failing command does not abort the script; the exit status of
+.B gosh
+is the one of the last command.
+.PP
+Because
+.B gosh
+supports
+.BR \-c ,
+.BR ssh (1),
+.BR scp (1)
+and
+.BR rsync (1)
+work when it is used as login shell.
+.SH STARTUP FILES
+Startup files are executed in the running shell, so variables and
+aliases defined there stay in effect.
+.TP
+Login shells
+read
+.I /etc/gosh/profile
+and
+.IR ~/.gosh_profile .
+.TP
+Interactive shells
+read
+.I /etc/gosh/goshrc
+and
+.IR ~/.goshrc .
+.PP
+An interactive login shell reads the profile files first, then the goshrc
+files. Scripts and
+.B \-c
+read no startup files unless
+.B gosh
+is a login shell. Missing files are skipped; errors are reported with file
+name and line number and the remaining lines still run. Files of other
+shells such as
+.I /etc/profile
+or
+.I ~/.bashrc
+are not read.
+.SH SYNTAX
+.SS Quoting
+.TP
+.B \(aq...\(aq
+Everything is literal.
+.TP
+.B \(dq...\(dq
+Variables and command substitutions are expanded, the result stays one
+word.
+.TP
+.B \e
+Escapes the next character.
+.SS Variables
+.TP
+.I name\fB=\fPvalue
+Set a variable. All variables are exported to the environment of started
+programs. The value is not split into words and not expanded as a pattern;
+variables, command substitutions and
+.B ~
+(at the start, after
+.B =
+and after
+.BR : )
+are expanded.
+.TP
+.I name\fB=\fPvalue command
+Set the variable only for
+.IR command .
+.TP
+.BR $VAR ", " ${VAR}
+The value of
+.BR VAR .
+Using an unset variable is an error and aborts the command.
+.TP
+.B ${VAR:\-default}
+The value of
+.BR VAR ,
+or
+.I default
+if it is unset or empty. Use
+.B ${VAR:\-}
+for an empty default.
+.TP
+.B $?
+The exit status of the last command.
+.SS Command substitution
+.B $(\fIcommand\fP)
+is replaced by the output of
+.IR command ,
+which runs in a subshell. Trailing newlines are removed. Unquoted, the
+output is split into words at blanks and newlines; inside double quotes it
+stays one word. Wildcards and operators in the output are not interpreted.
+Backticks and arithmetic expansion are not supported.
+.SS Tilde and brace expansion
+.B ~
+and
+.B ~/path
+at the start of an unquoted word are replaced by the home directory.
+.PP
+Brace expansion generates several words from one:
+.B a{b,c}d
+becomes
+.BR "abd acd" ,
+.B {1..5}
+becomes
+.BR "1 2 3 4 5" ,
+.B {01..10..4}
+becomes
+.B 01 05 09
+and
+.B {a..e}
+becomes
+.BR "a b c d e" .
+Brace expansion happens before all other expansions.
+.SS Wildcards
+.B *
+matches any string,
+.B ?
+any single character,
+.B [abc]
+and
+.B [a\-z]
+one of the given characters and
+.B [!abc]
+(or
+.BR [^abc] )
+any character except those. Matches are sorted. Hidden files are only
+matched if the pattern starts with a dot. A pattern without match is kept
+unchanged. Quoted wildcards and values of variables are never expanded.
+.SS Command lists
+.TP
+.IB a " ; " b
+Run
+.IR a ,
+then
+.IR b .
+.TP
+.IB a " && " b
+Run
+.I b
+only if
+.I a
+succeeded.
+.TP
+.IB a " || " b
+Run
+.I b
+only if
+.I a
+failed.
+.TP
+.IB command " &"
+Run
+.I command
+in the background.
+.SS Pipes and redirections
+.TP
+.IB a " | " b
+Connect standard output of
+.I a
+to standard input of
+.IR b .
+The exit status is the one of
+.IR b .
+.TP
+.BI < " file"
+Read standard input from
+.IR file .
+.TP
+.BR > " \fIfile\fP, " >> " \fIfile\fP"
+Write (or append) standard output to
+.IR file .
+.TP
+.BR 2> " \fIfile\fP, " 2>> " \fIfile\fP"
+Write (or append) standard error to
+.IR file .
+.TP
+.B 2>&1
+Redirect standard error to where standard output goes.
+.TP
+.B >&2
+Redirect standard output to where standard error goes.
+.TP
+.BR &> " \fIfile\fP, " &>> " \fIfile\fP"
+Write (or append) standard output and standard error to
+.IR file .
+.PP
+Redirections are evaluated from left to right. Only file descriptors 0, 1
+and 2 are supported.
+.SS Control structures
+.nf
+\fBif\fP \fIlist\fP; \fBthen\fP \fIlist\fP; [\fBelif\fP \fIlist\fP; \fBthen\fP \fIlist\fP;] [\fBelse\fP \fIlist\fP;] \fBfi\fP
+\fBfor\fP \fIname\fP \fBin\fP \fIwords\fP; \fBdo\fP \fIlist\fP; \fBdone\fP
+\fBwhile\fP \fIlist\fP; \fBdo\fP \fIlist\fP; \fBdone\fP
+\fBuntil\fP \fIlist\fP; \fBdo\fP \fIlist\fP; \fBdone\fP
+\fB!\fP \fIcommand\fP
+.fi
+.PP
+Control structures may span several lines; an incomplete command shows
+the continuation prompt
+.BR "> " .
+.B !
+negates the exit status of a command. Control structures cannot be used
+in pipes, with redirections or in the background.
+.B case
+and functions are not supported.
+.SS Aliases
+In interactive shells, the first word of a command is replaced by its
+alias. If the alias value ends with a blank, the next word is checked for
+an alias as well.
+.B \e\fIname\fP
+or
+.B \(aq\fIname\fP\(aq
+skips the alias. Aliases are not used in scripts and with
+.BR \-c .
+.SH BUILTIN COMMANDS
+.TP
+.BR cd " [\fIdir\fP]"
+Change the directory; without argument to the home directory.
+.TP
+.B pwd
+Print the working directory.
+.TP
+.BR echo " [\fIargs\fP]"
+Print the arguments.
+.TP
+.BR exit " [\fIcode\fP], " quit " [\fIcode\fP]"
+Exit the shell with status
+.I code
+(default:
+.BR $? ).
+.TP
+.BI set " VAR" = value
+Set a variable.
+.TP
+.BI export " VAR" = value
+Export a variable.
+.TP
+.BI unset " VAR"
+Remove a variable.
+.TP
+.BI source " file\fR, \fP" ". " file
+Run the commands of
+.I file
+in the current shell.
+.TP
+.B jobs
+List background and stopped jobs.
+.TP
+.BR fg " [\fB%\fP\fIn\fP]"
+Continue job
+.I n
+(default: the current job) in the foreground.
+.TP
+.BR bg " [\fB%\fP\fIn\fP]"
+Continue stopped job
+.I n
+in the background.
+.TP
+.BR wait " [\fB%\fP\fIn\fP]"
+Wait for job
+.I n
+or for all background jobs.
+.TP
+.BR alias " [\fIname\fP[\fB=\fP\fIvalue\fP] ...]"
+Define or show aliases.
+.TP
+.BR unalias " \fIname\fP, " "unalias \-a"
+Remove an alias, or all aliases.
+.TP
+.B :
+Do nothing, exit status 0.
+.TP
+.BR break " [\fIn\fP], " continue " [\fIn\fP]"
+Leave the innermost (or
+.IR n -th)
+loop, or continue with its next iteration.
+.TP
+.B help
+Show a summary of builtins and features.
+.SH JOB CONTROL
+In interactive shells, each command line runs as a job in its own process
+group.
+.B Ctrl+Z
+stops the foreground job,
+.B Ctrl+C
+interrupts it.
+.BR jobs ,
+.BR fg ,
+.B bg
+and
+.B wait
+manage the jobs;
+.B %n
+or
+.I n
+refers to job
+.IR n ,
+.B %\-
+to the previous job. Finished background jobs are reported before the
+next prompt. Exiting with stopped jobs warns once.
+.SH INTERACTIVE USE
+.TP
+.B Up/Down
+Browse the command history.
+.TP
+.B Tab
+Complete commands, aliases and file names.
+.TP
+.B Ctrl+C
+Cancel the current line or command.
+.TP
+.B Ctrl+D
+Exit the shell.
+.PP
+Lines starting with a space are not saved in the history.
+.PP
+The prompt shows
+.IR user @ host : dir
+followed by
+.BR $ .
+If the last command failed, its exit status is shown as
+.BI [ N ]
+before the
+.BR $ .
+.SH ENVIRONMENT
+.TP
+.B GOSH_HISTFILE
+Path of the history file. If set to an empty value, no history is saved.
+.TP
+.B XDG_STATE_HOME
+Base directory of the default history file
+.IR $XDG_STATE_HOME/gosh/history .
+.TP
+.B GOSH_COLORS
+Prompt colors as colon-separated
+.IB key = code
+entries. Keys are
+.B user
+(default
+.BR 1;32 ),
+.B root
+.RB ( 1;31 ),
+.B path
+.RB ( 1;34 )
+and
+.B error
+.RB ( 1;31 );
+values are ANSI SGR codes, an empty value disables the color. Example:
+.B GOSH_COLORS=\(aquser=1;33:path=36\(aq
+.TP
+.B NO_COLOR
+If set, the prompt is not colored. Colors are also disabled with
+.B TERM=dumb
+or when the output is not a terminal.
+.TP
+.B HOME
+Used for
+.B ~
+and
+.B cd
+without argument.
+.TP
+.B PATH
+Directories searched for commands.
+.SH FILES
+.TP
+.I /etc/gosh/profile
+System-wide profile for login shells.
+.TP
+.I ~/.gosh_profile
+Personal profile for login shells.
+.TP
+.I /etc/gosh/goshrc
+System-wide startup file for interactive shells.
+.TP
+.I ~/.goshrc
+Personal startup file for interactive shells.
+.TP
+.I ~/.local/state/gosh/history
+Default history file (mode 0600).
+.SH EXIT STATUS
+The exit status of the last command, or the argument of
+.BR exit .
+Typical values:
+.TP
+.B 1
+General error.
+.TP
+.B 2
+Syntax error or invalid option.
+.TP
+.B 126
+Command not executable.
+.TP
+.B 127
+Command not found.
+.TP
+.BI 128+ n
+Command terminated by signal
+.I n
+(130 for Ctrl+C).
+.SH EXAMPLES
+.nf
+gosh \-c \(aqcd /srv && git log | head\(aq
+for f in *.log; do gzip "$f"; done
+cp config.yaml{,.bak}
+make > build.log 2>&1 || echo "failed: $?"
+LANG=C sort file
+alias ll=\(aqls \-l\(aq
+chsh \-s /usr/bin/gosh
+.fi
+.SH SEE ALSO
+.BR sh (1),
+.BR bash (1),
+.BR chsh (1),
+.BR shells (5)
+.SH AUTHOR
+Florian Walther <florian.walther@certainity.com>