Add rgl(1df)

3 files changed, 37 insertions, 0 deletions

diff --git a/README.markdown b/README.markdown
index 211ce5fe..559244a7 100644
--- a/README.markdown
+++ b/README.markdown
@@ -447,6 +447,7 @@ Installed by the `install-bin` target:
 *   `plmu(1df)` retrieves a list of installed modules from
     [`plenv`](https://github.com/tokuhirom/plenv), filters out any modules in
     `~/.plenv/non-cpan-modules`, and updates them all.
+*   `rgl(1df)` is a very crude interactive `grep(1)` loop.
 *   `shb(1df)` attempts to build shebang lines for scripts from `$PATH`.
 *   `spr(1df)` posts its input to the sprunge.us pastebin.
 *   `sshi(1df)` prints human-readable SSH connection details.
diff --git a/bin/rgl b/bin/rgl
new file mode 100755
index 00000000..03f1ba71
--- /dev/null
+++ b/bin/rgl
@@ -0,0 +1,17 @@
+#!/bin/sh
+# Read grep(1) patterns from input and search for them in the given files
+
+# Check the arguments
+if [ "$#" -eq 0 ] ; then
+    printf >&2 'rgl: Need at least one filename\n'
+    exit 2
+fi
+
+# Iterate over the patterns and search for each one; if the input is a terminal
+# include a slash prompt for the next pattern
+while { 
+    [ -t 0 ] && printf /
+    read -r pat
+} ; do
+    grep -- "$pat" "$@"
+done
diff --git a/man/man1/rgl.1df b/man/man1/rgl.1df
new file mode 100644
index 00000000..eb5b2905
--- /dev/null
+++ b/man/man1/rgl.1df
@@ -0,0 +1,19 @@
+.TH RGL 1df "September 2016" "Manual page for rgl"
+.SH NAME
+.B rgl
+\- search files for patterns read from stdin
+.SH SYNOPSIS
+.B rgl
+file
+.br
+.B rgl
+file1 file2 file3
+.br
+.B rgl
+file < patterns
+.SH DESCRIPTION
+.B rgl ("read, grep, loop") searches the files given in its arguments for each
+of the patterns given on standard input with grep(1). If it detects its input
+is a terminal, it provides a forward slash as a prompt for the next pattern.
+.SH AUTHOR
+Tom Ryder <tom@sanctum.geek.nz>