Add man pages

Makefile

@@ -2,12 +2,15 @@ DESTDIR ?=
 PREFIX ?= /usr/local
 EXEC_PREFIX ?= $(PREFIX)
 BINDIR ?= $(EXEC_PREFIX)/bin
+DATAROOTDIR ?= $(PREFIX)/share
+MANDIR ?= $(DATAROOTDIR)/man
 
 CFLAGS += -Os -g -Wall -Wextra -pedantic
 CPPFLAGS +=
 LDFLAGS +=
 
 BINS := plainhex plainunhex
+MAN1S := plainhex.1 plainunhex.1
 
 .SUFFIXES:
 .SUFFIXES: .c .o
@@ -24,8 +27,9 @@ plainunhex: plainunhex.o
 .c.o:
 	$(CC) -c $(CFLAGS) $(CPPFLAGS) -o $@ $<
 
-install: $(BINS)
+install: $(BINS) $(MAN1S)
 	install -D -m 755 -t '$(DESTDIR)$(BINDIR)' $(BINS)
+	install -D -m 644 -t '$(DESTDIR)$(MANDIR)/man1' $(MAN1S)
 
 uninstall:
 	cd $(DESTDIR)$(BINDIR) && rm $(BINS)

plainhex.1

@@ -0,0 +1,17 @@
+.Dd Aug 17, 2019
+.Dt PLAINHEX 1
+.Os
+.Sh NAME
+.Nm plainhex
+.Nd most basic possible hexdump
+.Sh SYNOPSIS
+.Nm
+.Sh DESCRIPTION
+.Nm
+reads bytes from stdin and writes them hex-encoded to stdout.
+There is no line-wrapping, padding, or field separation.
+The hexdump is ended with a single newline.
+.Sh EXIT STATUS
+.Ex -std
+.Sh SEE ALSO
+.Xr plainunhex 1

plainunhex.1

@@ -0,0 +1,18 @@
+.Dd Aug 17, 2019
+.Dt PLAINUNHEX 1
+.Os
+.Sh NAME
+.Nm plainunhex
+.Nd most basic possible hexundump
+.Sh SYNOPSIS
+.Nm
+.Sh DESCRIPTION
+.Nm
+reads pairs of hex digits from the stdin and writes the corresponding bytes
+to stdout.
+Both lowercase and uppercase hex digits are supported.
+Everything that is not a hex digit is ignored.
+.Sh EXIT STATUS
+.Ex -std
+.Sh SEE ALSO
+.Xr plainhex 1