I'm very new to shell scripting and i've been struggling with the following shell script. I'm posting the script and the commands i used below for your consideration please help me with the mistake i made.
#
#
#
DBG=0
RLS=0
ALL=0
CLN=0
print_help_uu()
{
echo "Usage: $0 -D -R -A -C ";
echo "Where -C clean the debug project builds";
echo " -D to build in DEBUG config";
echo " -R to build in RELEASE config";
echo " -A to build in both configs";
return
}
#
# Main procedure start here
#
# Check for sufficent args
#
if [ $# -eq 0 ] ; then
print_help_uu
exit 1
fi
#
# Function to clean the project
#
clean()
{
if ["$DBG"="1"]; then
echo "Cleaning debug"
if ["$RLS"="1"]; then
echo "cleaning release + debug"
else
echo "This is bad"
fi
fi
if ["$RLS"="1"]; then
echo "Cleaning release "
fi
return
}
while getopts "DRAC" opt
do
case "$opt" in
D) DBG=1;;
R) RLS=1;;
A) DBG=1;RLS=1;;
C) CLN=1;;
\?) print_help_uu; exit 1;;
esac
clean
done
I'm posting the commands i used to run it and the errors i got when using those commands.
----------
./BuildProject.sh -D
./BuildProject.sh: line 36: [1=1]: command not found
./BuildProject.sh: line 46: [0=1]: command not found
-----------
sh BuildProject.sh -D
BuildProject.sh: 63: [1=1]: not found
BuildProject.sh: 63: [0=1]: not found
-----------
sh ./BuildProject.sh -D
./BuildProject.sh: 63: [1=1]: not found
./BuildProject.sh: 63: [0=1]: not found
I tried to solve it in soo many ways and googled a lot before posting here. But all my trials went in vain. Please tell me where i'm doing the mistake since i'm new to shell scripting.
Thanks in Advance.
[ is a command, but you are trying to invoke the command [1=1]. Add some whitespace:
if [ "$DBG" = "1" ]; then
Try to change ["$DBG"="1"] (and similar if statements) into this: [ "$DBG" = "1" ]
i.e. add some space.
i think it's a "SPACE" problem : try
if [ "$DBG" = "1" ]; then
instead of
if ["$DBG"="1"]; then
It's a space issue indeed.
VAR=VALUE
is only for variable declaration in shell, while
VAR = VALUE
is only for variable testing. It's tricky, you just have to get used to it.
It Worked after adding some extra spaces into it. Thank you all. Is it a Scripting rule to put those spaces in between the variables?? I think i ignored that rule. Thanks for your time.
Related
Let's pretend I'm running something like this:
jq -nr --arg target /tmp \
'(["echo","Hello, world"]|#sh)+">\($target)/sample.txt"' \
| sh
Everything is fine unless I forgot to pass variable $target:
$ jq -nr '(["echo","Hello, world"]|#sh)+">\($target)/sample.txt"'
jq: error: $target is not defined at <top-level>, line 1:
(["echo","Hello, world"]|#sh)+">\($target)/sample.txt"
jq: 1 compile error
How can I catch this and use default value?
I've tried:
$target?
($target)?
try $target catch null
$target? // null
But it seems to be parsing-time error, which obviously can't be caught at runtime. Have I've missed any dynamic syntax?
I've found that command-line arguments can be found in $ARGS.name, but there are two drawbacks:
This was introduced in version 1.6, but I have 1.5 on CentOS 7.
It doesn't catch locally defined variables.
Assuming you need to do something more useful with jq than write 'Hello World' over a text file. I propose the following,
Maybe we can learn some programming tips from Jesus:
"Give to Caesar what belongs to Caesar, and give to God what belongs to God"
Suppose that Caesar is bash shell and God is jq, bash is appropriate to work and test the existence of files, directories and environment variables, jq is appropriate to process information in json format.
#!/bin/bash
dest_folder=$1
#if param1 is not given, then the default is /tmp:
if [ -z $dest_folder ]; then dest_folder=/tmp ; fi
echo destination folder: $dest_folder
#check if destination folder exists
if [ ! -d $dest_folder ]
then
echo "_err_ folder not found"
exit 1
fi
jq -nr --arg target $dest_folder '(["echo","Hello, world"]|#sh)+">\($target)/sample.txt"' | sh
#if the file is succesfully created, return 0, if not return 1
if [ -e "$dest_folder/sample.txt" ]
then
echo "_suc_ file was created ok"
exit 0
else
echo "_err_ when creating file"
exit 1
fi
Now you can include this script as a step in a more complex batch, because it is congruent with linux style, returning 0 on success.
Suppose, there are 4 different types of patterns(errors) in a log each may occur time to time. Eg: "timeout exception", "ldap error "," db error "," error four". Can any one place provide me a script about:- how to grep multiple patterns in a log every hour and if the script finds the any pattern then it should send alert to me only once, no duplicate alerts. Please help me. Thank you
#!/bin/bash
while true; do
export ERRORS=`cat YOUR_LOG_FILE | grep -e "(timeout exception)|(ldap error)|(db error)|(error four)"
if [ $ERRORS ]; then
# sendmail or any other kind of "alert" you prefer.
echo $ERRORS | sendmail "your#email.com"
fi
sleep 1h
done
Make a crontab entry that will run once an hour. That entry can call your script:
logfile=/path/to/logfile/application.out
function send_alert {
# Some sendmail or other tool to send your alert using the args
printf "I want to alert about %s" "$*"
}
# Solution only announcing errors without sending them
grep -qE "timeout exception|ldap error|db error|error four" ${logfile} &&
send_alert "grep found something"
# Solution sending number of errorlines
errorlinecount=$(grep -c "timeout exception|ldap error|db error|error four" )
if [ ${errorcount} -gt 0 ]; then
send_alert "grep found ${errorcount} disturbing lines"
fi
#!/bin/bash
LOCATION=$1
FILECOUNT=0
DIRCOUNT=0
if [ "$#" -lt "1" ]
then
echo "Usage: ./test2.sh <directory>"
exit 0
fi
I don't actually get what the If statement is saying can anyone help me to explain this?Thank you
$1 refers to the first argument of the bash file. In this case, you can pass your directory path by issuing the following command:
# ./test2.sh /path/of/your/directory
#!/bin/bash
LOCATION=$1 #first argument of the script
FILECOUNT=0
DIRCOUNT=0
if [ "$#" -lt "1" ] #if the number of argument(s) ($#) is less than 1
then
echo "Usage: ./test2.sh <directory>"
exit 0
fi
You can read this article for more information about parameter passing.
Hope it helps.
$1 is the first argument that is passed to the bash script. If you start the script like ./test2.sh argument1 argument2 the $1 will refer argument1.
The if-statement checks, if the count of arguments (that's the $#) is smaller than 1, then it will output the usage statement (as it seems you can't run the script without any argument).
I am using KornShell (ksh) on Solaris and currently my PS1 env var is:
PS1="${HOSTNAME}:\${PWD} \$ "
And the prompt displays: hostname:/full/path/to/current/directory $
However, I would like it to display: hostname:directory $
In other words, how can I display just the hostname and the name of the current directory, i.e. tmp or ~ or public_html etc etc?
From reading the ksh man page you want
PS1="${HOSTNAME}:\${PWD##*/} \$ "
Tested on default ksh on SunOS 5.8
Okay, a little old and a little late, but this is what I use in Kornshell:
PS1='$(print -n "`logname`#`hostname`:";if [[ "${PWD#$HOME}" != "$PWD" ]] then; print -n "~${PWD#$HOME}"; else; print -n "$PWD";fi;print "\n$ ")'
This makes a prompt that's equivalent to PS1="\u#\h:\w\n$ " in BASH.
For example:
qazwart#mybook:~
$ cd bin
qazwart#mybook:~/bin
$ cd /usr/local/bin
qazwart#mybook:/usr/local/bin
$
I like a two line prompt because I sometimes have very long directory names, and they can take up a lot of the command line. If you want a one line prompt, just leave off the "\n" on the last print statement:
PS1='$(print -n "`logname`#`hostname`:";if [[ "${PWD#$HOME}" != "$PWD" ]] then; print -n "~${PWD#$HOME}"; else; print -n "$PWD";fi;print "$ ")'
That's equivalent to PS1="\u#\h:\w$ " in BASH:
qazwart#mybook:~$ cd bin
qazwart#mybook:~/bin$ cd /usr/local/bin
qazwart#mybook:/usr/local/bin$
It's not quite as easy as setting up a BASH prompt, but you get the idea. Simply write a script for PS1 and Kornshell will execute it.
For Solaris and other Older Versions of Kornshell
I found that the above does not work on Solaris. Instead, you'll have to do it the real hackish way...
In your .profile, make sure that ENV="$HOME/.kshrc"; export ENV
is set. This is probably setup correctly for you.
In your .kshrc file, you'll be doing two things
You'll be defining a function called _cd. This function will change to the directory specified, and then set your PS1 variable based upon your pwd.
You'll be setting up an alias cd to run the _cd function.
This is the relevant part of the .kshrc file:
function _cd {
logname=$(logname) #Or however you can set the login name
machine=$(hostname) #Or however you set your host name
$directory = $1
$pattern = $2 #For "cd foo bar"
#
# First cd to the directory
# We can use "\cd" to evoke the non-alias original version of the cd command
#
if [ "$pattern" ]
then
\cd "$directory" "$pattern"
elif [ "$directory" ]
then
\cd "$directory"
else
\cd
fi
#
# Now that we're in the directory, let's set our prompt
#
$directory=$PWD
shortname=${directory#$HOME} #Possible Subdir of $HOME
if [ "$shortName" = "" ] #This is the HOME directory
then
prompt="~$logname" # Or maybe just "~". Your choice
elif [ "$shortName" = "$directory" ] #Not a subdir of $HOME
then
prompt="$directory"
else
prompt="~$shortName"
fi
PS1="$logname#$hostname:$prompt$ " #You put it together the way you like
}
alias cd="_cd"
This will set your prompt as the equivelent BASH PS1="\u#\h:\w$ ". It isn't pretty, but it works.
ENV=~/.kshrc, and then in your .kshrc:
function _cd {
\cd "$#"
PS1=$(
print -n "$LOGNAME#$HOSTNAME:"
if [[ "${PWD#$HOME}" != "$PWD" ]]; then
print -n "~${PWD#$HOME}"
else
print -n "$PWD"
fi
print "$ "
)
}
alias cd=_cd
cd "$PWD"
Brad
HOST=`hostname`
PS1='$(print -n "[${USER}#${HOST%%.*} ";[[ "$HOME" == "$PWD" ]] && print -n "~" ||([[ "${PWD##*/}" == "" ]] && print -n "/" || print -n "${PWD##*/}");print "]$")'
PS1=`id -un`#`hostname -s`:'$PWD'$
and...
if you work between two shells for most of your effort [ksh and bourne sh]
and desire a directory tracking display on your command line
then PWD can be substituted easily in ksh
and if you use /usr/xpg4/bin/sh for your sh SHELL, it will work there as well
Try this:
PS1="\H:\W"
More information on: How to: Change / Setup bash custom prompt, I know you said ksh, but I am pretty sure it will work.
I want to be able to tell if a command exists on any POSIX system from a shell script.
On Linux, I can do the following:
if which <command>; then
...snip...
fi
However, Solaris and MacOS which do not give an exit failure code when the command does not exist, they just print an error message to STDOUT.
Also, I recently discovered that the which command itself is not POSIX (see http://pubs.opengroup.org/onlinepubs/9699919799/idx/utilities.html)
Any ideas?
command -v is a POSIX specified command that does what which does.
It is defined to to return >0 when the command is not found or an error occurs.
You could read the stdout/stderr of "which" into a variable or an array (using backticks) rather than checking for an exit code.
If the system does not have a "which" or "where" command, you could also grab the contents of the $PATH variable, then loop over all the directories and search for the given executable. That's essentially what which does (although it might use some caching/optimization of $PATH results).
One which utility is available as shell script in the Git repository of debianutils package of Debian Linux. The script seems to be POSIX compatible and you could use it, if you take into account copyright and license. Note that there have been some controversy whether or not and how the which utility should be deprecated; (at time of writing) current version in Git shows deprecation message whereas an earlier version added later removed -s option to enable silent operation.
command -v as such is problematic as it may output a shell function name, an alias definition, a keyword, a builtin or a non-executable file path. On the other hand some path(s) output by which would not be executed by shell if you run the respective argument as such or as an argument for command. As an alternative for using the which script, a POSIX shell function using command -v could be something like
#!/bin/sh
# Argument $1 should be the basename of the command to be searched for.
# Outputs the absolute path of the command with that name found first in
# a directory listed in PATH environment variable, if the name is not
# shadowed by a special built-in utility, a regular built-in utility not
# associated with a PATH search, or a shell reserved word; otherwise
# outputs nothing and returns 1. If this function prints something for
# an argument, it is the path of the same executable as what 'command'
# would execute for the same argument.
executable() {
if cmd=$(unset -f -- "$1"; command -v -- "$1") \
&& [ -z "${cmd##/*}" ] && [ -x "$cmd" ]; then
printf '%s\n' "$cmd"
else
return 1
fi
}
Disclaimer: Note that the script using command -v above does not find an executable whose name equals a name of a special built-in utility, a regular built-in utility not associated with a PATH search, or a shell reserved word. It might not find an executable either in case if there is non-executable file and executable file available in PATH search.
A function_command_exists for checking if a command exists:
#!/bin/sh
set -eu
function_command_exists() {
local command="$1"
local IFS=":" # paths are delimited with a colon in $PATH
# iterate over dir paths having executables
for search_dir in $PATH
do
# seek only in dir (excluding subdirs) for a file with an exact (case sensitive) name
found_path="$(find "$search_dir" -maxdepth 1 -name "$command" -type f 2>/dev/null)"
# (positive) if a path to a command was found and it was executable
test -n "$found_path" && \
test -x "$found_path" && \
return 0
done
# (negative) if a path to an executable of a command was not found
return 1
}
# example usage
echo "example 1";
command="ls"
if function_command_exists "$command"; then
echo "Command: "\'$command\'" exists"
else
echo "Command: "\'$command\'" does not exist"
fi
command="notpresent"
if function_command_exists "$command"; then
echo "Command: "\'$command\'" exists"
else
echo "Command: "\'$command\'" does not exist"
fi
echo "example 2";
command="ls"
function_command_exists "$command" && echo "Command: "\'$command\'" exists"
command="notpresent"
function_command_exists "$command" && echo "Command: "\'$command\'" does not exist"
echo "End of the script"
output:
example 1
Command: 'ls' exists
Command: 'notpresent' does not exist
example 2
Command: 'ls' exists
End of the script
Note that even the set -eu that turns -e option for the script was used the script was executed to the last line "End of the script"
There is no Command: 'notpresent' does not exist in the example 2 because of the && operator so the execution of echo "Command: "\'$command\'" does not exist" is skipped but the execution of the script continues till the end.
Note that the function_command_exists does not check if you have a right to execute the command. This needs to be done separately.
Solution with command -v <command-to-check>
#!/bin/sh
set -eu;
# check if a command exists (Yes)
command -v echo > /dev/null && status="$?" || status="$?"
if [ "${status}" = 127 ]; then
echo "<handle not found 1>"
fi
# check if a command exists (No)
command -v command-that-does-not-exists > /dev/null && status="$?" || status="$?"
if [ "${status}" = 127 ]; then
echo "<handle not found 2>"
fi
produces:
<handle not found 2>
because echo was found at the first example.
Solution with running a command and handling errors including command not found.
#!/bin/sh
set -eu;
# check if a command exists (No)
command -v command-that-does-not-exist > /dev/null && status="$?" || status="$?"
if [ "${status}" = 127 ]; then
echo "<handle not found 2>"
fi
# run command and handle errors (no problem expected, echo exist)
echo "three" && status="$?" || status="$?"
if [ "${status}" = 127 ]; then
echo "<handle not found 3>"
elif [ "${status}" -ne 0 ]; then
echo "<handle other error 3>"
fi
# run command and handle errors (<handle not found 4> expected)
command-that-does-not-exist && status="$?" || status="$?"
if [ "${status}" = 127 ]; then
echo "<handle not found 4>"
elif [ "${status}" -ne 0 ]; then
echo "<handle other error 4>"
fi
# run command and handle errors (command exists but <handle other error 5> expected)
ls non-existing-path && status="$?" || status="$?"
if [ "${status}" = 127 ]; then
echo "<handle not found 5>"
elif [ "${status}" -ne 0 ]; then
echo "<handle other error 5>"
fi
produces:
<handle not found 2>
three
./function_command_exists.sh: 34: ./function_command_exists.sh: command-that-does-not-exist: not found
<handle not found 4>
ls: cannot access 'non-existing-path': No such file or directory
<handle other error 5>
The following works in both bash and zsh and avoids both functions and aliases.
It returns 1 if the binary is not found.
bin_path () {
if [[ -n ${ZSH_VERSION:-} ]]; then
builtin whence -cp "$1" 2> /dev/null
else
builtin type -P "$1"
fi
}