Fix formatting

Author: cholmcc

run/SimExamples/HepMC/README.md

@@ -3,7 +3,7 @@
 /doxy -->
 
 Here are pointers on how to use `GeneratorHepMC` selected by the
-option `-g hepmc` for `o2-sim`. 
+option `-g hepmc` for `o2-sim`.
 
 ## Reading HepMC files
 
@@ -19,31 +19,32 @@ Examples of such programs are
 - ... and many others
 
 Please refer to the documentation of these for more on how to make
-event files in the HepMC format. 
+event files in the HepMC format.
 
 To make a simulation reading from the file `events.hepmc`, do
     o2-sim -g hepmc --configKeyValues "HepMC.fileName=events.hepmc"	...
 
-See also [`read.sh`](read.sh) 
+See also [`read.sh`](read.sh).
 
 ## Reading HepMC events from child process
 `GeneratorHepMC` can not only read HepMC events from a file, but can
 also spawn an child EG to produce events.  Suppose we have a program
 named `eg` which is some EG that writes HepMC event records to the
 standard output.  Then we can execute a simulation using this external
 EG by
-    o2-sim -g hepmc --configKeyValues "HepMC.progCmd=eg" 
 
-See also [`child.sh`](child.sh) 
+    o2-sim -g hepmc --configKeyValues "HepMC.progCmd=eg"
 
-There are some requirements on the program `eg`: 
+See also [`child.sh`](child.sh). 
+
+There are some requirements on the program `eg`:
 
 - It _must_ write the HepMC event structures to standard output
-  (`/dev/stdout`). 
+  (`/dev/stdout`).
 - It may _not_ write other information to standard output.
 - It _must_ accept the option `-n n-events` to set the number of
-  events to produce to `n-events`. 
-  
+  events to produce to `n-events`.
+
 If a program does not adhere to these requirements, it will often be
 simple enough to make a small wrapper script that enforce this.  For
 example, `crmc` will write a lot of information to standard output.
@@ -56,7 +57,7 @@ The `sed` command selects lines that begin with `HepMC::`, or one
 of single characters `E` (event), `A` (attribute), `U` (units), `W`
 (weight), `V` (vertex), or `P` (particle) followed by a space.  This
 should in most cases be enough to filter out extra stuff written on
-standard output. 
+standard output.
 
 The script above also passes any additional command line options on to
 `crmc` via `$@`.  We can utilise this with `o2-sim` to set options to
@@ -68,15 +69,15 @@ using DpmJET, we can do
 
 ### Implementation details
 
-Internally `GeneratorHepMC` 
+Internally `GeneratorHepMC`
 
 1. creates a unique temporary file name in the working directory,
 2. then creates a FIFO (or named pipe, see
    [Wikipedia](https://en.wikipedia.org/wiki/Named_pipe)),
-3. builds a command line, e.g., 
+3. builds a command line, e.g.,
+
+        eg options > fifo-name &
 
-      eg options > fifo-name & 
-	  
 4. and executes that command line
 
 ## The future
@@ -89,48 +90,49 @@ particular
 - HepMC event structures can be read from any file format supported by
   HepMC it self (see
   [here](http://hepmc.web.cern.ch/hepmc/group__IO.html) and
-  [here](http://hepmc.web.cern.ch/hepmc/group__factory.html). 
-  
-- New options that can be specified in `--configKeyValues` 
+  [here](http://hepmc.web.cern.ch/hepmc/group__factory.html).
+
+- New options that can be specified in `--configKeyValues`
 
   - `HepMC.eventsToSkip=number` a number events to skip at the
-    beginning of each file read. 
-	
+    beginning of each file read.
+
   - `FileOrCmd.fileNames=list` a comma separated list of HepMC files
-    to read
+    to read.
+
   - `FileOrCmd.cmd=command line` a command line to execute as a
     background child process.  If this is set (not the empty string),
-    then `FileOrCmd.fileNames` is ignored. 
-	
+    then `FileOrCmd.fileNames` is ignored.
+
   - A number of keys that specifies the command line option switch
     that the child program accepts for certain things.  If any of
     these are set to the empty string, then that switch and
-    corresponding option value is not passed to the child program. 
-	
+    corresponding option value is not passed to the child program.
+
     - `FileOrCmd.outputSwitch=switch` (default `>`) to specify output
       file.  The default of `>` assumes that the program write HepMC
-      events, and _only_ those, to standard output. 
-	  
+      events, and _only_ those, to standard output.
+
     - `FileOrCmd.seedSwitch=switch` (default `-s`) to specify the
       random number generator seed. The value passed is selected by
-      the `o2-sim` option `--seed` 
-	  
+      the `o2-sim` option `--seed`
+
     - `FileOrCmd.bMaxSwitch=switch` (default `-b`) to specify the
        upper limit on the impact parameters sampled.  The value passed
-       is selected by the `o2-sim` option `--bMax` 
-	   
+       is selected by the `o2-sim` option `--bMax`
+
     - `FileOrCmd.nEventsSwitch=switch` (default `-n`) to specify the
        number of events to generate.  The value passed is selected by
        the `o2-sim` option `--nEvents` or (`-n`)
-	   
+
     - `FileOrCmd.backgroundSwitch=switch` (default `&`) to specify how
       the program is put in the background.  Typically this should be
       `&`, but a program may itself fork to the background.
 
 - Some options are no longer available
   - `HepMC.fileName` - use `FileOrCmd.fileNames`
-  - `HepMC.progCmd` - use `FileOrCmd.cmd` 
-  
+  - `HepMC.progCmd` - use `FileOrCmd.cmd`
+
 The command line build will now be
 
 > _commandLine_ _nEventsSwitch_ _nEvents_ _seedSwitch_ _seed_