Script Help (Bash) SOLVED

[Cameron Simpson]

| > On Sat, Sep 28, 2013 at 6:21 AM, Frank Murphy <frankly3d at gmail.com>
| > wrote: [...]
| > > #!/bin/bash

Unless I really need bash, I use:

  #!/bin/sh

More portable. You'll be surprised how little bash actually gives
you in scripting scenarios.

| > > ## Download no-bebug rawhide kernel
| > > /usr/bin/cd /var/cache/yum/x86_64/20/fedora-rawhide-kernel-nodebug-source/packages
| > > && \ /usr/bin/reposync  --source -n =fedora-rawhide-kernel-nodebug
| > > kernel && \

Two remarks:

  I tend to write lines like the above as:

    cmd1 \
    && cmd2

  If you write:

    cmd1 && \
    cmd2

  and accidentally put something after the slosh (such as some
  spaces), the former layout will cause a syntax error (alerting
  you) while the latter layout will quietly not work quite as
  expected.

Second:

  I almost invariably put:

    set -ue

  at the top of my scripts. This turns on -u: abort on an undefined
  variable, VERY handy for catching assignment mistakes and -e:
  abort on error, which means abort when any command has a non-zero
  exit status _that has not been checked_.

  This would let you write your script like this:

    set -ue
    cd /var/cache/yum/x86_64/20/fedora-rawhide-kernel-nodebug-source/packages
    /usr/bin/reposync  --source -n =fedora-rawhide-kernel-nodebug

  and so on without all the tedious "&&" stuff.

  It is surprisingly useful and easy to code under this regime,
  and catches a long of simple mistakes.

Cheers,
-- 
Cameron Simpson <cs at zip.com.au>

Gross power consumption [...] such as 3D graphics and MPEG-2 are the
two applications which consume a disproportionate amount of power [...]
eating close to 18 watts of power. Close behind is Microsoft Word 7.0,
which consumes close to 16 watts of power.