shell脚本的调试
1. 运行脚本时，添加-x选项
$ bash -x script-name
$ bash -x domains.sh
$ sh -x script_name
2. 在脚本中开启编译选项
#!/bin/bash
clear
# turn on debug mode
set -x
for f in *
do
file $f
done
# turn OFF debug mode
set +x
ls
# more commands
说明：
set -x Prints the statements after interpreting metacharacters and variables
set +x Stops the printing of statements
set -v Prints the statements before interpreting metacharacters and variables
set -f Disables file name generation (using metacharacters)
3. 解释器参数
#!/bin/bash -xv
#!/bin/sh -x
4.使用Debug变量和函数来实现
#!/bin/bash
_DEBUG="on"
function DEBUG()
{
[ "$_DEBUG" == "on" ] && $@
}
DEBUG echo 'Reading files'
for i in *
do
grep 'something' $i > /dev/null
[ $? -eq 0 ] && echo "Found in $i file"
done
DEBUG set -x
a=2
b=3
c=$(( $a + $b ))
DEBUG set +x
echo "$a + $b = $c"
5. 使用日志打印
（1.）下载log4shell.sh脚本
https://github.com/fredpalmer/log4bash/blob/master/log4bash.sh
（2.）日志打印
#!/usr/bin/env bash
source log4bash.sh
log "This is regular log message... log and log_info do the same thing";
log_warning "Luke ... you turned off your targeting computer";
log_info "I have you now!";
log_success "You're all clear kid, now let's blow this thing and go home.";
log_error "One thing's for sure, we're all gonna be a lot thinner.";
# If you have figlet installed -- you'll see some big letters on the screen!
log_captains "What was in the captain's toilet?";
# If you have the "say" command (e.g. on a Mac)
log_speak "Resistance is futile";