有没有办法让庆典变成了一种过于冗长模式,其中,这样,当它运行一个shell脚本,它呼应了它会运行之前运行的命令? 也就是说,以便它可以看到已运行的命令(以及它们的输出),类似的输出make
?
也就是说,如果运行像一个shell脚本
echo "Hello, World"
我想下面的输出
echo "Hello, World"
Hello, World
或者,是否有可能写称为bash函数echo_and_run
将输出一个命令,然后运行它?
$ echo_and_run echo "Hello, World"
echo "Hello, World"
Hello, World
Answer 1:
你可以让自己的功能, echo
之前调用命令eval
。
击也有一个调试功能。 一旦您set -x
bash将执行前显示的每个命令。
cnicutar@shell:~/dir$ set -x
cnicutar@shell:~/dir$ ls
+ ls --color=auto
a b c d e f
Answer 2:
为了回答你问题的第二部分,这里有你想要做什么shell函数:
echo_and_run() { echo "$*" ; "$@" ; }
我用类似这样:
echo_and_run() { echo "\$ $*" ; "$@" ; }
它打印$
在命令前(它看起来像一个shell提示,并使其更清晰,它是一个命令)。 当我想展示一些(但不是全部),它在执行命令我有时在脚本中使用此。
正如其他人所说,它失去了引号:
$ echo_and_run echo "Hello, world"
$ echo Hello, world
Hello, world
$
但我不认为有,以避免任何好办法; 外壳去掉引号之前echo_and_run
都有机会看到它们。 你可以写一个脚本,将检查包含空格和其他shell元字符的参数,并根据需要(这仍然不一定匹配引号,你实际键入)加上引号。
Answer 3:
这是可能的使用bash的printf
结合%q
格式说明逃跑,使空格都被保留的参数:
function echo_and_run {
echo "$" "$@"
eval $(printf '%q ' "$@") < /dev/tty
}
Answer 4:
要添加到别人的实现,这是我的基本的脚本样板,包括参数解析(如果你切换冗长水平,这是非常重要的)。
#!/bin/sh
# Control verbosity
VERBOSE=0
# For use in usage() and in log messages
SCRIPT_NAME="$(basename $0)"
ARGS=()
# Usage function: tells the user what's up, then exits. ALWAYS implement this.
# Optionally, prints an error message
# usage [{errorLevel} {message...}
function usage() {
local RET=0
if [ $# -gt 0 ]; then
RET=$1; shift;
fi
if [ $# -gt 0 ]; then
log "[$SCRIPT_NAME] ${@}"
fi
log "Describe this script"
log "Usage: $SCRIPT_NAME [-v|-q]" # List further options here
log " -v|--verbose Be more verbose"
log " -q|--quiet Be less verbose"
exit $RET
}
# Write a message to stderr
# log {message...}
function log() {
echo "${@}" >&2
}
# Write an informative message with decoration
# info {message...}
function info() {
if [ $VERBOSE -gt 0 ]; then
log "[$SCRIPT_NAME] ${@}"
fi
}
# Write an warning message with decoration
# warn {message...}
function warn() {
if [ $VERBOSE -gt 0 ]; then
log "[$SCRIPT_NAME] Warning: ${@}"
fi
}
# Write an error and exit
# error {errorLevel} {message...}
function error() {
local LEVEL=$1; shift
if [ $VERBOSE -gt -1 ]; then
log "[$SCRIPT_NAME] Error: ${@}"
fi
exit $LEVEL
}
# Write out a command and run it
# vexec {minVerbosity} {prefixMessage} {command...}
function vexec() {
local LEVEL=$1; shift
local MSG="$1"; shift
if [ $VERBOSE -ge $LEVEL ]; then
echo -n "$MSG: "
local CMD=( )
for i in "${@}"; do
# Replace argument's spaces with ''; if different, quote the string
if [ "$i" != "${i/ /}" ]; then
CMD=( ${CMD[@]} "'${i}'" )
else
CMD=( ${CMD[@]} $i )
fi
done
echo "${CMD[@]}"
fi
${@}
}
# Loop over arguments; we'll be shifting the list as we go,
# so we keep going until $1 is empty
while [ -n "$1" ]; do
# Capture and shift the argument.
ARG="$1"
shift
case "$ARG" in
# User requested help; sometimes they do this at the end of a command
# while they're building it. By capturing and exiting, we avoid doing
# work before it's intended.
-h|-\?|-help|--help)
usage 0
;;
# Make the script more verbose
-v|--verbose)
VERBOSE=$((VERBOSE + 1))
;;
# Make the script quieter
-q|--quiet)
VERBOSE=$((VERBOSE - 1))
;;
# All arguments that follow are non-flags
# This should be in all of your scripts, to more easily support filenames
# that start with hyphens. Break will bail from the `for` loop above.
--)
break
;;
# Something that looks like a flag, but is not; report an error and die
-?*)
usage 1 "Unknown option: '$ARG'" >&2
;;
#
# All other arguments are added to the ARGS array.
*)
ARGS=(${ARGS[@]} "$ARG")
;;
esac
done
# If the above script found a '--' argument, there will still be items in $*;
# move them into ARGS
while [ -n "$1" ]; do
ARGS=(${ARGS[@]} "$1")
shift
done
# Main script goes here.
后来...
vexec 1 "Building myapp.c" \
gcc -c myapp.c -o build/myapp.o ${CFLAGS}
注意:这将不包括管道命令; 你需要在bash -c那些各种各样的东西,或者将它们分开成中间变量或文件。
Answer 5:
可以添加到两个有用的shell选项bash
命令行或通过set
在脚本或交互式会话命令:
- -v打印外壳的输入行被读取。
- -x展开每个简单的命令,之后
for
命令, case
命令, select
命令,或算术for
命令,显示扩展后的值PS4
,接着所述命令和它的膨胀的参数或相关联的单词列表。
Answer 6:
对于额外的时间戳和I / O信息,考虑annotate-output
从Debian的的devscripts软件包中的命令:
annotate-output echo hello
输出:
13:19:08 I: Started echo hello
13:19:08 O: hello
13:19:08 I: Finished with exitcode 0
现在找一个不存在 ,并注意E中的文件:用于STDERR输出:
annotate-output ls nosuchfile
输出:
13:19:48 I: Started ls nosuchfile
13:19:48 E: ls: cannot access 'nosuchfile': No such file or directory
13:19:48 I: Finished with exitcode 2
Answer 7:
创建可执行文件(+ x)的命名与下文提到的简单的shell脚本“echo_and_run”基地脚本!
#!/bin/bash
echo "$*"
$@
$ ./echo_and_run“回声你好,世界”
echo Hello, World
Hello, World
或者干脆用一个衬垫bash函数 。
echo_and_run() { echo "\$ $*" ; "$@" ; }
甚至这种变异会工作:
function echo_and_run {
echo "$" "$@"
eval $(printf '%q ' "$@") < /dev/tty
}
然而,cnicutar的计算策略来set -x
是可靠的,强烈推荐。
文章来源: Echo command, and then run it? (Like make)