Shell script to execute set of commands in given directories - bash

I have written following shell script to execute given set of commands in the directory of each package. It is supposed to stop if any command fails. It should also show the command output on the console.
It takes 3 arguments with options
'-b' base directory of packages
'-c' comma separated list of commands
'-p' comma separated list of packages (individual
directories)
Shell Script
#!/bin/bash
#Function to execute a command
executeCommand(){
printf "\n**** Executing Command: '$1' *****\n\n"
$1
return $?
}
#Initialize the variables with command line arguments
while getopts "c:p:b:" options; do
case $options in
b ) set -f # disable glob
IFS=, # split on space characters
base_directory=$OPTARG ;; # use the split+glob operator
c ) set -f # disable glob
IFS=, # split on space characters
commands=($OPTARG) ;; # use the split+glob operator
p ) set -f # disable glob
IFS=, # split on space characters
packages=($OPTARG) ;; # use the split+glob operator
esac
done
#Iterate over all packages
for (( i = 0; i < ${#packages[#]} ; i++ )); do
#Go to each package directory
if executeCommand "cd ${base_directory}${packages[$i]}"; then
#Execute all the commands one by one for current package
for (( j = 0; j < ${#commands[#]} ; j++ )); do
if executeCommand "${commands[$j]}"; then
echo "Successfully Executed the Command"
else
break 2;
fi
done
else
break;
fi
done
If I execute it with following arguments it gives me an error that No Such File or directory however, if I manually execute cd /local/workplace/directory1 it goes to the directory1
Execution and Error
~/bb-slds.sh \
-c "build clean","build package" \
-p directory1,directory1 \
-b /local/workplace/
**** Executing Command: 'cd /local/workplace/directory1' *****
/home/jramay/bb-slds.sh: line 6: cd /local/workplace/directory1: No such file or directory
It works fine if I don't use getopts and instead initialize the variables as below.
base_directory="/local/workplace/"
declare -a commands=(
"build clean"
"build package"
)
declare -a packages=(
"directory1"
"directory2"
)

This was a tricky one. :)
You changed IFS during the getopts loop, and never changed it back to the old value. So when you write:
$1
in executeCommand, it doesn't treat the space as a separator between cd and its argument.
You need to set it back to the default value after the getopts is done:
IFS=$' \t\n'
The set -f changes persist after getopts as well. You should probably just do it once before the loop, then put
set +f
after it.

Related

How can I invoke another program's bash completion handler for a single subcommand of my program?

Context
I have an arduino-cli wrapper script named ino that reads target/build configuration from:
JSON files located in the sketch directory
Command-line flags/arguments
It then constructs and exec's the corresponding arduino-cli command-line.
Problem
As a convenience wrapper script, ino isn't intended to support every feature of arduino-cli. So for those tasks that ino doesn't automate, the user can instead invoke arduino-cli indirectly using the cli subcommand of ino.
For example, if the user types the following commands:
% ino cli update
% ino cli core list --all
The ino script will take everything following cli and simply append them to the arduino-cli executable. So they would be equivalent to the following commands:
% arduino-cli update
% arduino-cli core list --all
Since arduino-cli has nice bash completion for all of its subcommands and flags, I would like to hijack the same completion functionality for my ino cli subcommand.
What I've tried
The accepted answers here:
How do I autocomplete nested, multi-level subcommands?
Multi Level Bash Completion
These helped me understand how to identify the current subcommand and discriminate the completion results based upon it.
However, I couldn't figure out how to then invoke the arduino-cli completion handler using the remaining args.
Completion handler derived from accepted answer here:
How do I get bash completion for command aliases?
See my ino completion handler based on that answer below (Reference 1).
This question/answer isn't quite the same, because they can basically just install a completion handler on their alias. I'm needing to "install" one on an argument to a command/alias.
This almost seems to work. Try it with xtrace option enabled (set -x), and you can see the arduino-cli command-line is appearing in the args ... but following ino at position $0.
E.g., given ino cli core list --all to the wrapper handler, the arduino-cli handler receives ino arduino-cli core list --all. Not sure how to get rid of $0!
Reference
ino completion wrapper derived from alias-based wrappers
joinstr() {
local d=${1-} f=${2-}
shift 2 && printf %s "$f" "${#/#/$d}"
}
complete-subcmd() {
[[ ${#} -gt 2 ]] || {
printf "usage:\n\tcomplete-subcmd src-command... -- comp-func dst-command...\n"
return 1
}
# parse the command-line by splitting it into two command-lines
# of variable length, src-command and dst-command:
# 1. src-command is the trigger that invokes the real completion
# handler, comp-func.
# 2. dst-command is the leading args of the command-line passed
# to the real completion handler, comp-func, to produce the
# resulting completion choices.
unset -v dstparse
local -a srccmd dstcmd
local func
while [[ ${#} -gt 0 ]]; do
case "${1}" in
--)
# when we reach the delimiter, also shift in comp-func as
# the next argument (the real completion handler).
dstparse=1
shift
func=${1:-}
;;
*)
# if we aren't processing the delimiter, then all other
# args are appended to either src-command or dst-command.
if [[ -z ${dstparse} ]]; then
srccmd+=( "${1}" )
else
dstcmd+=( "${1}" )
fi
;;
esac
shift
done
# if the completer is dynamic and not yet loaded, try to load it
# automatically using the given command
if [[ $( type -t "${func}" ) != function ]]; then
type -p _completion_loader &> /dev/null &&
_completion_loader "${dstcmd[#]}"
fi
local wrap=$( joinstr _ "${srccmd[#]}" | tr -d -c '[A-Za-z_]' )
# replace our args with dst-command followed by whatever remains
# from the invoking command-line.
eval "
function _${wrap} {
(( COMP_CWORD+=$(( ${#dstcmd[#]} )) ))
COMP_WORDS=( "${dstcmd[#]}" \${COMP_WORDS[#]:1} )
"${func}"
return 0
}
"
# install this wrapper handler on the first word in src-command
complete -F "_${wrap}" "${srccmd[0]}"
}
complete-subcmd ino cli -- __start_arduino-cli arduino-cli
completion.bash from arduino-cli
# bash completion V2 for arduino-cli -*- shell-script -*-
__arduino-cli_debug()
{
if [[ -n ${BASH_COMP_DEBUG_FILE:-} ]]; then
echo "$*" >> "${BASH_COMP_DEBUG_FILE}"
fi
}
# Macs have bash3 for which the bash-completion package doesn't include
# _init_completion. This is a minimal version of that function.
__arduino-cli_init_completion()
{
COMPREPLY=()
_get_comp_words_by_ref "$#" cur prev words cword
}
# This function calls the arduino-cli program to obtain the completion
# results and the directive. It fills the 'out' and 'directive' vars.
__arduino-cli_get_completion_results() {
local requestComp lastParam lastChar args
# Prepare the command to request completions for the program.
# Calling ${words[0]} instead of directly arduino-cli allows to handle aliases
args=("${words[#]:1}")
requestComp="${words[0]} __completeNoDesc ${args[*]}"
lastParam=${words[$((${#words[#]}-1))]}
lastChar=${lastParam:$((${#lastParam}-1)):1}
__arduino-cli_debug "lastParam ${lastParam}, lastChar ${lastChar}"
if [ -z "${cur}" ] && [ "${lastChar}" != "=" ]; then
# If the last parameter is complete (there is a space following it)
# We add an extra empty parameter so we can indicate this to the go method.
__arduino-cli_debug "Adding extra empty parameter"
requestComp="${requestComp} ''"
fi
# When completing a flag with an = (e.g., arduino-cli -n=<TAB>)
# bash focuses on the part after the =, so we need to remove
# the flag part from $cur
if [[ "${cur}" == -*=* ]]; then
cur="${cur#*=}"
fi
__arduino-cli_debug "Calling ${requestComp}"
# Use eval to handle any environment variables and such
out=$(eval "${requestComp}" 2>/dev/null)
# Extract the directive integer at the very end of the output following a colon (:)
directive=${out##*:}
# Remove the directive
out=${out%:*}
if [ "${directive}" = "${out}" ]; then
# There is not directive specified
directive=0
fi
__arduino-cli_debug "The completion directive is: ${directive}"
__arduino-cli_debug "The completions are: ${out[*]}"
}
__arduino-cli_process_completion_results() {
local shellCompDirectiveError=1
local shellCompDirectiveNoSpace=2
local shellCompDirectiveNoFileComp=4
local shellCompDirectiveFilterFileExt=8
local shellCompDirectiveFilterDirs=16
if [ $((directive & shellCompDirectiveError)) -ne 0 ]; then
# Error code. No completion.
__arduino-cli_debug "Received error from custom completion go code"
return
else
if [ $((directive & shellCompDirectiveNoSpace)) -ne 0 ]; then
if [[ $(type -t compopt) = "builtin" ]]; then
__arduino-cli_debug "Activating no space"
compopt -o nospace
else
__arduino-cli_debug "No space directive not supported in this version of bash"
fi
fi
if [ $((directive & shellCompDirectiveNoFileComp)) -ne 0 ]; then
if [[ $(type -t compopt) = "builtin" ]]; then
__arduino-cli_debug "Activating no file completion"
compopt +o default
else
__arduino-cli_debug "No file completion directive not supported in this version of bash"
fi
fi
fi
if [ $((directive & shellCompDirectiveFilterFileExt)) -ne 0 ]; then
# File extension filtering
local fullFilter filter filteringCmd
# Do not use quotes around the $out variable or else newline
# characters will be kept.
for filter in ${out[*]}; do
fullFilter+="$filter|"
done
filteringCmd="_filedir $fullFilter"
__arduino-cli_debug "File filtering command: $filteringCmd"
$filteringCmd
elif [ $((directive & shellCompDirectiveFilterDirs)) -ne 0 ]; then
# File completion for directories only
# Use printf to strip any trailing newline
local subdir
subdir=$(printf "%s" "${out[0]}")
if [ -n "$subdir" ]; then
__arduino-cli_debug "Listing directories in $subdir"
pushd "$subdir" >/dev/null 2>&1 && _filedir -d && popd >/dev/null 2>&1 || return
else
__arduino-cli_debug "Listing directories in ."
_filedir -d
fi
else
__arduino-cli_handle_standard_completion_case
fi
__arduino-cli_handle_special_char "$cur" :
__arduino-cli_handle_special_char "$cur" =
}
__arduino-cli_handle_standard_completion_case() {
local tab comp
tab=$(printf '\t')
local longest=0
# Look for the longest completion so that we can format things nicely
while IFS='' read -r comp; do
# Strip any description before checking the length
comp=${comp%%$tab*}
# Only consider the completions that match
comp=$(compgen -W "$comp" -- "$cur")
if ((${#comp}>longest)); then
longest=${#comp}
fi
done < <(printf "%s\n" "${out[#]}")
local completions=()
while IFS='' read -r comp; do
if [ -z "$comp" ]; then
continue
fi
__arduino-cli_debug "Original comp: $comp"
comp="$(__arduino-cli_format_comp_descriptions "$comp" "$longest")"
__arduino-cli_debug "Final comp: $comp"
completions+=("$comp")
done < <(printf "%s\n" "${out[#]}")
while IFS='' read -r comp; do
COMPREPLY+=("$comp")
done < <(compgen -W "${completions[*]}" -- "$cur")
# If there is a single completion left, remove the description text
if [ ${#COMPREPLY[*]} -eq 1 ]; then
__arduino-cli_debug "COMPREPLY[0]: ${COMPREPLY[0]}"
comp="${COMPREPLY[0]%% *}"
__arduino-cli_debug "Removed description from single completion, which is now: ${comp}"
COMPREPLY=()
COMPREPLY+=("$comp")
fi
}
__arduino-cli_handle_special_char()
{
local comp="$1"
local char=$2
if [[ "$comp" == *${char}* && "$COMP_WORDBREAKS" == *${char}* ]]; then
local word=${comp%"${comp##*${char}}"}
local idx=${#COMPREPLY[*]}
while [[ $((--idx)) -ge 0 ]]; do
COMPREPLY[$idx]=${COMPREPLY[$idx]#"$word"}
done
fi
}
__arduino-cli_format_comp_descriptions()
{
local tab
tab=$(printf '\t')
local comp="$1"
local longest=$2
# Properly format the description string which follows a tab character if there is one
if [[ "$comp" == *$tab* ]]; then
desc=${comp#*$tab}
comp=${comp%%$tab*}
# $COLUMNS stores the current shell width.
# Remove an extra 4 because we add 2 spaces and 2 parentheses.
maxdesclength=$(( COLUMNS - longest - 4 ))
# Make sure we can fit a description of at least 8 characters
# if we are to align the descriptions.
if [[ $maxdesclength -gt 8 ]]; then
# Add the proper number of spaces to align the descriptions
for ((i = ${#comp} ; i < longest ; i++)); do
comp+=" "
done
else
# Don't pad the descriptions so we can fit more text after the completion
maxdesclength=$(( COLUMNS - ${#comp} - 4 ))
fi
# If there is enough space for any description text,
# truncate the descriptions that are too long for the shell width
if [ $maxdesclength -gt 0 ]; then
if [ ${#desc} -gt $maxdesclength ]; then
desc=${desc:0:$(( maxdesclength - 1 ))}
desc+="…"
fi
comp+=" ($desc)"
fi
fi
# Must use printf to escape all special characters
printf "%q" "${comp}"
}
__start_arduino-cli()
{
local cur prev words cword split
COMPREPLY=()
# Call _init_completion from the bash-completion package
# to prepare the arguments properly
if declare -F _init_completion >/dev/null 2>&1; then
_init_completion -n "=:" || return
else
__arduino-cli_init_completion -n "=:" || return
fi
__arduino-cli_debug
__arduino-cli_debug "========= starting completion logic =========="
__arduino-cli_debug "cur is ${cur}, words[*] is ${words[*]}, #words[#] is ${#words[#]}, cword is $cword"
# The user could have moved the cursor backwards on the command-line.
# We need to trigger completion from the $cword location, so we need
# to truncate the command-line ($words) up to the $cword location.
words=("${words[#]:0:$cword+1}")
__arduino-cli_debug "Truncated words[*]: ${words[*]},"
local out directive
__arduino-cli_get_completion_results
__arduino-cli_process_completion_results
}
if [[ $(type -t compopt) = "builtin" ]]; then
complete -o default -F __start_arduino-cli arduino-cli
else
complete -o default -o nospace -F __start_arduino-cli arduino-cli
fi
# ex: ts=4 sw=4 et filetype=sh
UPDATE2:
After I posted this I checked your links and after seeing the accepted answer here, I was thinking I am just old and forget that I just copied this code from that link, and it wasn't me who wrote it. Even the example used there is the same, but investigating the code further, it looks I did write this and used a different approach, and maybe this will help you understand what's going on. As I mentioned at the bottom UPDATE1 section: you need to tune the COMP variables then call the original function
Original:
I wrote an 'alias wrapper' script a couple of years ago.
The idea is to use the original bash completion with aliases even with parameters.
For example:
alias apti='apt-get install'
source alias-completion-wrapper _apt_get apti apt-get install
#here _apt_get is the original completion function
Now you can use tab to complete the package name after apti just like after apt-get install
#alias-completion-wrapper
#Example: . alias-completion-wrapper _apt_get apti apt-get install
comp_function_name="$1"
ali="$2"
shift 2
x="$#"
function_name=`echo _$# |tr ' ' _`
function="
function $function_name {
_completion_loader $1
(( COMP_CWORD += $# - 1 ))
COMP_WORDS=( $# \"\${COMP_WORDS[#]:1}\")
COMP_LINE=\"\${COMP_WORDS[#]}\"
let COMP_POINT=\${COMP_POINT}-${#ali}+${#x}
$comp_function_name
return 0
}"
eval "$function"
complete -F $function_name $ali
unset function function_name ali x
To be honest, I can't remember how it works and I didn't commented the script :)
But I think you will be able to tune this for your needs.
UPDATE1:
As I investigated the code a bit, it looks like the idea is to tune the COMP variables, then call the original function :)
UPDATE3:
I had some time, so the modification you need are:
This ${COMP_WORDS[#]} contains the current command line. ${COMP_WORDS[#]:1} cuts off the first word, which is originally the alias/command. As you want to use it after a parameter you have to cut off the parameter too.
COMP_WORDS=( $# \"\${COMP_WORDS[#]:2}\")
I don't see COMP_LINE and COMP_POINT in the other solution, but as I can recall without those, it doesn't worked well in certain circumstances. So I suppose you need:
COMP_LINE=\"\${COMP_WORDS[#]:1}\"
And here ${#ali} is the length of the command. You need to replace this with the length of your command with the parameter. eg,:"xcmd prm" -> 8 (count the space too)
let COMP_POINT=\${COMP_POINT}-${#ali}+${#x}
Not sure about (( COMP_CWORD += $# - 1 )) either remove the -1 or use -2 or leave it as it is :)
After the modifications, just change the eval to echo and remove the complete -F line. And source the script as described. This way it will echo the function what you can insert into your completion script.

How can I export function in a function in bash?

I am learning bash. And I would like to make a function which wrap another function in a temporal script file and execute it with sudo -u command in sub-shell.
The problem I encountered is the generated script cannot find the wrapped function although it is exported in the wrap function.
I append test cords below. Someone who finds problems, please let me know. Thank you very much.
main.sh
source "./display.sh"
source "./sudo_wrap.sh"
display_func "load success"
sudo_wrap_func '' 'display_func' '3' '4 5'
output, display.sh, sudo_wrap.sh and generated temporal file are appended below,
output
display_func : load success
export -f display_func
30481: line 5: display_func: command not found
display.sh
function display_func() {
echo "display_func : $#"
}
sudo_wrap.sh
function sudo_wrap_func() {
local sudo_user="${1:-root}"
local function_name="${2:?'function_name is null string.'}"
shift 2
local func_augs=( "$#" )
local script
# *** script : header ***
script="#!/bin/bash\n"
script="${script}\n"
# *** script : making augments for function ***
script="${script}augs=("
for aug in "${func_augs[#]}"
do
if [[ "${aug}" =~ [[:blank:]] ]]; then
script=" ${script} \"${aug}\""
else
script=" ${script} ${aug}"
fi
done
script="${script})\n"
local tmp_script_file="${RANDOM}"
echo -e "${script}" >> "${tmp_script_file}"
# *** script : calling function with augments ***
echo -e "${function_name} \"\${augs[#]}\"\n" >> "${tmp_script_file}"
echo "export -f "${function_name}"" >&2
export -f "${function_name}"
sudo -u"${sudo_user}" bash "${tmp_script_file}"
rm "${tmp_script_file}"
}
temporally generated file (in this case, file name is 30481)
#!/bin/bash
augs=( 3 "4 5")
display_func "${augs[#]}"
As I said in a comment, the basic problem is that sudo cleans its environment (including both variables and functions) before running the command (/script) as another user. This can be overridden with sudo -E, but only if it's explicitly allowed in /etc/sudoers.
But the problem is not insoluble; you just have to include the definition of the function in the script, so it gets recreated in that environment. bash even has a convenient command, declare -f display_func, that prints the function definition in the appropriate form (and declare -p variable does the same for variables). So you can use those to add the appropriate definitions to the script.
Here's a script I wrote to do this. I made a few other changes vs. your script: I take -u username to specify a different user to run as (so you don't have to pass '' as the first argument if you don't want to specify a different user). I also added -f functionname and -v variablename to "export" additional function and variable definitions into the script (in case the main function depends on them). I also create the temp script file in /tmp, and change ownership if necessary so it'll be readable by the other user.
#!/bin/bash
me="$(basename "$0")"
usage() {
echo "Usage: $me [-u user] [-f otherfunction] [-v variablename] function [args...]" >&2
}
tmp_script_file=$(mktemp "/tmp/${me}.XXXXXXXXXXXX") || {
echo "Error creating temporary script file" >&2
exit 1
}
echo "#!/bin/bash" > "$tmp_script_file" # Not actually needed, since we'll run it with "bash"
# Parse the command options; "-u" gets stored for later, but "-f" and "-v" write
# the relevant declarations to the script file as we go.
sudo_user=""
while getopts u:f:v: OPT; do
case "$OPT" in
u)
sudo_user="$OPTARG" ;;
f)
declare -f "$OPTARG" >>"$tmp_script_file" || {
echo "Error saving definition of function $OPTARG" >&2
exit 1
} ;;
v)
declare -p "$OPTARG" >>"$tmp_script_file" || {
echo "Error saving definition of variable $OPTARG" >&2
exit 1
} ;;
?) usage; exit 1 ;;
esac
done
shift $(($OPTIND-1))
if (( $# == 0 )); then # No actual command specified
usage
exit 1
fi
# Write the main function itself into the script
declare -f "$1" >>"$tmp_script_file" || {
echo "Error saving definition of function $1" >&2
exit 1
}
# Then the command to run it, with arguments quoted/escaped as
# necessary.
printf "%q " "$#" >>"$tmp_script_file"
# the printf above won't write a newline, so add it by hand
echo >>"$tmp_script_file"
# If the script will run as someone other than root, change ownership of the
# script so the target user can read it
if [[ -n "$sudo_user" ]]; then
sudo chown "$sudo_user" "$tmp_script_file"
fi
# Now launch the script, suitably sudo'ed
sudo ${sudo_user:+ -u "$sudo_user"} bash "$tmp_script_file"
# Clean up
sudo rm "$tmp_script_file"
Here's an example of using it:
$ foo() { echo "foo_variable is '$foo_variable'"; }
$ bar() { echo "Running the function bar as $(whoami)"; echo "Arguments: $*"; foo; }
$ export -f foo bar # need to export these so the script can see them
$ export foo_variable='Whee!!!' # ditto
$ # Run the function directly first, so see what it does
$ bar 1 2 3
Running the function bar as gordon
Arguments: 1 2 3
foo_variable is 'Whee!!!'
$ # Now run it as another user with the wrapper script
$ ./sudo_wrap.sh -f foo -v foo_variable -u deenovo bar 1 2 3
Running the function bar as deenovo
Arguments: 1 2 3
foo_variable is 'Whee!!!'
Note that you could remove the need to export the functions and variables by either running the script with source or making it a function, but doing that would require changes to how $me is defined, the usage function, replacing all those exits with returns, and maybe some other things I haven't thought of.

How to run my bash functions in terminal using a parent name?

* the wording of the question is terrible, sorry!
I have some bash functions I create
test() {echo "hello wold"}
test2() {echo "hello wold"}
Then in my .bashrc I source the file that has the above function . ~/my_bash_scripts/testFile
In the terminal I can run test and get hello world.
is there a way for me to add parent variable that holds all my functions together. For example personal test, personal test2.
Similar to every other gem out there, I downloaded a tweeter one. All it's methods are followed by the letter t, as in t status to write a status, instead of just status
You are asking about writing a command-line program. Just a simple one here:
#!/usr/bin/env bash
if [[ $# -eq 0 ]]; then
echo "no command specified"
exit
elif [[ $# -gt 1 ]]; then
echo "only one argument expected"
exit
fi
case "$1" in
test)
echo "hello, this is test1"
;;
test2)
echo "hello, this is test2"
;;
*)
echo "unknown command: $1"
;;
esac
Then save it and make it an executable by run chmod +x script.sh, and in your .bashrc file, add alias personal="/fullpath/to/the/script.sh".
This is just very basic and simple example using bash and of course you can use any language you like, e.g. Python, Ruby, Node e.t.c.
Use arguments to determine final outputs.
You can use "$#" for number of arguments.
For example,
if [ $# -ne 2 ]; then
# TODO: print usage
exit 1
fi
Above code exits if arguments not euqal to 2.
So below bash program
echo $#
with
thatscript foo bar baz quux
will output 4.
Finally you can combine words to determine what to put stdout.
If you want to flag some functions as your personal functions; no, there is no explicit way to do that, and essentially, all shell functions belong to yourself (although some may be defined by your distro maintainer or system administrator as system-wide defaults).
What you could do is collect the output from declare -F at the very top of your personal shell startup file; any function not in that list is your personal function.
SYSFNS=$(declare -F | awk '{ a[++i] = $3 }
END { for (n=1; n<=i; n++) printf "%s%s", (n>1? ":" : ""), a[n] }')
This generates a variable SYSFNS which contains a colon-separated list of system-declared functions.
With that defined, you can check out which functions are yours:
myfns () {
local fun
declare -F |
while read -r _ _ fun; do
case :$SYSFNS: in *:"$fun":*) continue;; esac
echo "$fun"
done
}

How to execute a file that is located in $PATH

I am trying to execute a hallo_word.sh that is stored at ~/bin from this script that is stored at my ~/Desktop. I have made both scripts executable. But all the time I get the problem message. Any ideas?
#!/bin/sh
clear
dir="$PATH"
read -p "which file you want to execute" fl
echo ""
for fl in $dir
do
if [ -x "$fl" ]
then
echo "executing=====>"
./$fl
else
echo "Problem"
fi
done
This line has two problems:
for fl in $dir
$PATH is colon separated, but for expects whitespace separated values. You can change that by setting the IFS variable. This changes the FIELD SEPARATOR used by tools like for and awk.
$fl contains the name of the file you want to execute, but you overwrite its value with the contents of $dir.
Fixed:
#!/bin/sh
clear
read -p "which file you want to execute" file
echo
IFS=:
for dir in $PATH ; do
if [ -x "$dir/$file" ]
then
echo "executing $dir/$file"
exec "$dir/$file"
fi
done
echo "Problem"
You could also be lazy and let a subshell handle it.
PATH=(whatever) bash command -v my_command
if [ $? -ne 0 ]; then
# Problem, could not be found.
else
# No problem
fi
There is no need to over-complicate things.
command(1) is a builtin command that allows you to check if a command exists.
The PATH value contains all the directories in which executable files can be run without explicit qualification. So you can just call the command directly.
#!/bin/sh
clear
# r for raw input, e to use readline, add a space for clarity
read -rep "Which file you want to execute? " fl || exit 1
echo ""
"$fl" || { echo "Problem" ; exit 1 ; }
I quote the name as it could have spaces.
To test if the command exists before execution use type -p
#!/bin/sh
clear
# r for raw input, e to use readline, add a space for clarity
read -rep "Which file you want to execute? " fl || exit 1
echo ""
type -p "$fq" >/dev/null || exit 1
"$fl" || { echo "Problem" ; exit 1 ; }

Bash Programming Passing Argument

I am currently learning bash programming and dont really understand why the passing argument for me is not working.
i have a script like this
#!/bin/bash
# the following environment variables must be set before running this script
# SIM_DIR name of directory containing armsim
# TEST_DIR name of the directory containing this script and the expected outputs
# LOG_DIR name of the directory that your output is written to by the run_test2 script
# ARMSIM_VERBOSE set to "-v" for verbose logging or leave unset
# First check the environment variables are set
giveup=0
if [[ ${#SIM_DIR} -eq 0 || ${#TEST_DIR} -eq 0 || ${#LOG_DIR} -eq 0 ]] ; then
echo One or more of the following environment variables must be set:
echo SIM_DIR, TEST_DIR, LOG_DIR
giveup=1
fi
# Now check the verbose flag
if [[ ${#ARMSIM_VERBOSE} != 0 && "x${ARMSIM_VERBOSE}" != "x-v" ]] ; then
echo ARMSIM_VERBOSE must be unset, empty or set to -v
giveup=1
fi
# Stop if environment is not set up
if [ ${giveup} -eq 1 ] ; then
exit 0
fi
cd ${TEST_DIR}
for i in test2-*.sh; do
echo "**** Running test ${i%.sh} *****"
./$i > ${LOG_DIR}/${i%.sh}.log
done
When I run the .sh file and pass in 3 example argument as below:-
$ ./run_test2 SIM_DIR TEST_DIR LOG_DIR
It still show: One or more of the following environment variables must be set:
SIM_DIR, TEST_DIR, LOG_DIR
Can anyone guide me on this? Thank you.
That's not how it's intended to work. The environment variables must be set beforehand either in the script or in the terminal like
export SIM_DIR=/home/someone/simulations
export TEST_DIR=/home/someone/tests
export LOG_DIR=/home/someone/logs
./run_test2
If you use these variables frequently, you might want to export them in ~/.bashrc. The syntax is identical to the exports in the above example.
Environment variables aren't really arguments in the sense I understand from your question/example. It sounds to me like you want to give arguments to a function/script, if you do that you can find your arguments in $1-9 (I think bash supports even more, unsure), the number of arguments are stored in $#
Example function that expects two arguments:
my_func() {
if [ $# -ne 2 ]; then
printf "You need to give 2 arguments\n"
return
fi
printf "Your first argument: %s\n" "$1"
printf "Your second argument: $s\n" "$2"
}
# Call the functionl like this
my_func arg1 arg2

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