You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
54 lines
1.2 KiB
54 lines
1.2 KiB
#!/bin/sh |
|
# |
|
# This script takes a filename as input and writes the current date to the |
|
# file. If the file already exists, it will not be overwritten unless the '-f' |
|
# (or '--force') flag is given. |
|
# |
|
# This script demonstrates several types of shFlags functionality. |
|
# - declaration of the FLAGS_HELP variable to customize the help output |
|
# - direct calling of the flags_help() function for script controlled usage |
|
# output |
|
# - handling of non-flag type command-line arguments that follow the flags |
|
# |
|
# Try the following: |
|
# $ ./write_date.sh now.out |
|
# $ cat now.out |
|
# |
|
# $ ./write_date.sh now.out |
|
# $ cat now.out |
|
# |
|
# $ ./write_date.sh -f now.out |
|
# $ cat now.out |
|
|
|
# source shflags |
|
. ../src/shflags |
|
|
|
# configure shflags |
|
DEFINE_boolean 'force' false 'force overwriting' 'f' |
|
FLAGS_HELP="USAGE: $0 [flags] filename" |
|
|
|
|
|
write_date() |
|
{ |
|
date >"$1" |
|
} |
|
|
|
die() |
|
{ |
|
[ $# -gt 0 ] && echo "error: $@" >&2 |
|
flags_help |
|
exit 1 |
|
} |
|
|
|
|
|
# parse the command-line |
|
FLAGS "$@" || exit 1 |
|
eval set -- "${FLAGS_ARGV}" |
|
|
|
# check for filename |
|
[ $# -gt 0 ] || die 'filename missing' |
|
filename=$1 |
|
|
|
[ -f "${filename}" -a ${FLAGS_force} -eq ${FLAGS_FALSE} ] \ |
|
&& die 'filename exists; not overwriting' |
|
write_date "${filename}"
|
|
|