I received this excellent answer on how to convert a zsh function to a fish function. Now I have another question. How do I call that function from another function, passing on the argument?
I have tried this:
function ogf
echo "Cloning, your editor will open when clone has completed..."
source (env TARGET_DIRECTORY=~/students EDITOR=$EDITOR clone_git_file -ts $argv[1] | psub)
end
function wogf
env EDITOR=webstorm ogf "$argv[1]"
end
but I get "env: ogf: No such file or directory".
The goal is only to change the EDITOR environment variable for this one execution, and then call ogf.
The env command can only run other external commands. It cannot call shell builtins or functions; regardless whether the shell is fish, bash, or something else. The solution is to define the function being called with the --no-scope-shadowing flag and use set -l in the calling function:
function ogf --no-scope-shadowing
echo "Cloning, your editor will open when clone has completed..."
source (env TARGET_DIRECTORY=~/students EDITOR=$EDITOR clone_git_file -ts $argv[1] | psub)
end
function wogf
set -l EDITOR webstorm
ogf $argv
end
Another option would be to write your function to use its own arguments, as follows:
function ogf
echo "Cloning, your editor will open when clone has completed..."
source (env TARGET_DIRECTORY=~/students EDITOR=$argv[2] clone_git_file -ts $argv[1] | psub)
end
function wogf
ogf $argv[1] 'webstorm'
end
Maybe this is a simpler example on how to call another function while passing arguments:
function foo
bar "hello" "world"
end
function bar
echo $argv[1]
echo $argv[2]
end
Then calling foo will print:
$ foo
hello
world
Related
I recently upgraded to fish 3.0.1 via Homebrew 2.0.1 on MacOS Mojave 10.14.2. Since the upgrade, the following error message appears every time fish starts:
contains: Unknown option '-gx'
/usr/local/Cellar/fish/3.0.1/share/fish/config.fish (line 426):
if not contains $entry $result
^
in function '__fish_macos_set_env'
called on line 228 of file /usr/local/Cellar/fish/3.0.1/share/fish/config.fish
with parameter list 'PATH /etc/paths /etc/paths.d'
from sourcing file /usr/local/Cellar/fish/3.0.1/share/fish/config.fish
called during startup
contains - test if a word is present in a list
Synopsis
contains [OPTIONS] KEY [VALUES...]
contains: Type 'help contains' for related documentation
contains: Unknown option '-e'
/usr/local/Cellar/fish/3.0.1/share/fish/config.fish (line 426):
if not contains $entry $result
^
in function '__fish_macos_set_env'
called on line 228 of file /usr/local/Cellar/fish/3.0.1/share/fish/config.fish
with parameter list 'PATH /etc/paths /etc/paths.d'
from sourcing file /usr/local/Cellar/fish/3.0.1/share/fish/config.fish
called during startup
contains - test if a word is present in a list
Synopsis
contains [OPTIONS] KEY [VALUES...]
contains: Type 'help contains' for related documentation
My first reflex was to have a look in the offending file, namely /usr/local/Cellar/fish/3.0.1/share/fish/config.fish, but this file is only 306 lines long, and therefore does not seem to contain the infamous line 426. I am copying this file below, in case it proves useful:
# Main file for fish command completions. This file contains various
# common helper functions for the command completions. All actual
# completions are located in the completions subdirectory.
#
# Set default field separators
#
set -g IFS \n\ \t
set -qg __fish_added_user_paths
or set -g __fish_added_user_paths
#
# Create the default command_not_found handler
#
function __fish_default_command_not_found_handler
printf "fish: Unknown command %s\n" (string escape -- $argv[1]) >&2
end
if status --is-interactive
# The user has seemingly explicitly launched an old fish with too-new scripts installed.
if not contains -- "string" (builtin -n)
set -g __is_launched_without_string 1
# XXX nostring - fix old fish binaries with no `string' builtin.
# When executed on fish 2.2.0, the `else' block after this would
# force on 24-bit mode due to changes to in test behavior.
# These "XXX nostring" hacks were added for 2.3.1
set_color --bold
echo "You appear to be trying to launch an old fish binary with newer scripts "
echo "installed into" (set_color --underline)"$__fish_data_dir"
set_color normal
echo -e "\nThis is an unsupported configuration.\n"
set_color yellow
echo "You may need to uninstall and reinstall fish!"
set_color normal
# Remove this code when we've made it safer to upgrade fish.
else
# Enable truecolor/24-bit support for select terminals
# Ignore Screen and emacs' ansi-term as they swallow the sequences, rendering the text white.
if not set -q STY
and not string match -q -- 'eterm*' $TERM
and begin
set -q KONSOLE_PROFILE_NAME # KDE's konsole
or string match -q -- "*:*" $ITERM_SESSION_ID # Supporting versions of iTerm2 will include a colon here
or string match -q -- "st-*" $TERM # suckless' st
or test -n "$VTE_VERSION" -a "$VTE_VERSION" -ge 3600 # Should be all gtk3-vte-based terms after version 3.6.0.0
or test "$COLORTERM" = truecolor -o "$COLORTERM" = 24bit # slang expects this
end
# Only set it if it isn't to allow override by setting to 0
set -q fish_term24bit
or set -g fish_term24bit 1
end
end
else
# Hook up the default as the principal command_not_found handler
# in case we are not interactive
function __fish_command_not_found_handler --on-event fish_command_not_found
__fish_default_command_not_found_handler $argv
end
end
#
# Set default search paths for completions and shellscript functions
# unless they already exist
#
set -g __fish_config_dir ~/.config/fish
if set -q XDG_CONFIG_HOME
set __fish_config_dir $XDG_CONFIG_HOME/fish
end
set -l userdatadir ~/.local/share
if set -q XDG_DATA_HOME
set userdatadir $XDG_DATA_HOME
end
# __fish_data_dir, __fish_sysconf_dir, __fish_help_dir, __fish_bin_dir
# are expected to have been set up by read_init from fish.cpp
# Grab extra directories (as specified by the build process, usually for
# third-party packages to ship completions &c.
set -l __extra_completionsdir
set -l __extra_functionsdir
set -l __extra_confdir
if test -f $__fish_data_dir/__fish_build_paths.fish
source $__fish_data_dir/__fish_build_paths.fish
end
# Set up function and completion paths. Make sure that the fish
# default functions/completions are included in the respective path.
if not set -q fish_function_path
set fish_function_path $__fish_config_dir/functions $__fish_sysconf_dir/functions $__extra_functionsdir $__fish_data_dir/functions
end
if not contains -- $__fish_data_dir/functions $fish_function_path
set fish_function_path $fish_function_path $__fish_data_dir/functions
end
if not set -q fish_complete_path
set fish_complete_path $__fish_config_dir/completions $__fish_sysconf_dir/completions $__extra_completionsdir $__fish_data_dir/completions $userdatadir/fish/generated_completions
end
if not contains -- $__fish_data_dir/completions $fish_complete_path
set fish_complete_path $fish_complete_path $__fish_data_dir/completions
end
# This cannot be in an autoload-file because `:.fish` is an invalid filename on windows.
function :
# no-op function for compatibility with sh, bash, and others.
# Often used to insert a comment into a chain of commands without having
# it eat up the remainder of the line, handy in Makefiles.
end
#
# This is a Solaris-specific test to modify the PATH so that
# Posix-conformant tools are used by default. It is separate from the
# other PATH code because this directory needs to be prepended, not
# appended, since it contains POSIX-compliant replacements for various
# system utilities.
#
if test -d /usr/xpg4/bin
if not contains -- /usr/xpg4/bin $PATH
set PATH /usr/xpg4/bin $PATH
end
end
# Add a handler for when fish_user_path changes, so we can apply the same changes to PATH
function __fish_reconstruct_path -d "Update PATH when fish_user_paths changes" --on-variable fish_user_paths
set -l local_path $PATH
for x in $__fish_added_user_paths
set -l idx (contains --index -- $x $local_path)
and set -e local_path[$idx]
end
set -g __fish_added_user_paths
if set -q fish_user_paths
for x in $fish_user_paths[-1..1]
if set -l idx (contains --index -- $x $local_path)
set -e local_path[$idx]
else
set -g __fish_added_user_paths $__fish_added_user_paths $x
end
set local_path $x $local_path
end
end
set -xg PATH $local_path
end
#
# Launch debugger on SIGTRAP
#
function fish_sigtrap_handler --on-signal TRAP --no-scope-shadowing --description "Signal handler for the TRAP signal. Launches a debug prompt."
breakpoint
end
#
# Whenever a prompt is displayed, make sure that interactive
# mode-specific initializations have been performed.
# This handler removes itself after it is first called.
#
function __fish_on_interactive --on-event fish_prompt
__fish_config_interactive
functions -e __fish_on_interactive
end
# Set the locale if it isn't explicitly set. Allowing the lack of locale env vars to imply the
# C/POSIX locale causes too many problems. Do this before reading the snippets because they might be
# in UTF-8 (with non-ASCII characters).
__fish_set_locale
# "." command for compatibility with old fish versions.
function . --description 'Evaluate contents of file (deprecated, see "source")' --no-scope-shadowing
if test (count $argv) -eq 0
# Uses tty directly, as isatty depends on "."
and tty 0>&0 >/dev/null
echo "source: '.' command is deprecated, and doesn't work with STDIN anymore. Did you mean 'source' or './'?" >&2
return 1
else
source $argv
end
end
# Upgrade pre-existing abbreviations from the old "key=value" to the new "key value" syntax.
# This needs to be in share/config.fish because __fish_config_interactive is called after sourcing
# config.fish, which might contain abbr calls.
if not set -q __fish_init_2_3_0
if set -q fish_user_abbreviations
set -l fab
for abbr in $fish_user_abbreviations
set fab $fab (string replace -r '^([^ =]+)=(.*)$' '$1 $2' -- $abbr)
end
set fish_user_abbreviations $fab
end
set -U __fish_init_2_3_0
end
# macOS-ism: Emulate calling path_helper.
if command -sq /usr/libexec/path_helper
# Adapt construct_path from the macOS /usr/libexec/path_helper
# executable for fish; see
# https://opensource.apple.com/source/shell_cmds/shell_cmds-203/path_helper/path_helper.c.auto.html .
function __fish_macos_set_env -d "set an environment variable like path_helper does (macOS only)"
set -l result
for path_file in $argv[2] $argv[3]/*
if test -f $path_file
while read -l entry
if not contains $entry $result
set result $result $entry
end
end <$path_file
end
end
for entry in $$argv[1]
if not contains $entry $result
set result $result $entry
end
end
set -xg $argv[1] $result
end
__fish_macos_set_env 'PATH' '/etc/paths' '/etc/paths.d'
if [ -n "$MANPATH" ]
__fish_macos_set_env 'MANPATH' '/etc/manpaths' '/etc/manpaths.d'
end
functions -e __fish_macos_set_env
end
#
# Some things should only be done for login terminals
# This used to be in etc/config.fish - keep it here to keep the semantics
#
if status --is-login
#
# Put linux consoles in unicode mode.
#
if test "$TERM" = linux
if string match -qir '\.UTF' -- $LANG
if command -sq unicode_start
unicode_start
end
end
end
end
# Invoke this here to apply the current value of fish_user_path after
# PATH is possibly set above.
__fish_reconstruct_path
# Allow %n job expansion to be used with fg/bg/wait
# `jobs` is the only one that natively supports job expansion
function __fish_expand_pid_args
for arg in $argv
if string match -qr '^%\d+$' -- $arg
# set newargv $newargv (jobs -p $arg)
jobs -p $arg
if not test $status -eq 0
return 1
end
else
printf "%s\n" $arg
end
end
end
function bg
builtin bg (__fish_expand_pid_args $argv)
end
function fg
builtin fg (__fish_expand_pid_args $argv)
end
function kill
command kill (__fish_expand_pid_args $argv)
end
function wait
builtin wait (__fish_expand_pid_args $argv)
end
function disown
builtin disown (__fish_expand_pid_args $argv)
end
# As last part of initialization, source the conf directories.
# Implement precedence (User > Admin > Extra (e.g. vendors) > Fish) by basically doing "basename".
set -l sourcelist
for file in $__fish_config_dir/conf.d/*.fish $__fish_sysconf_dir/conf.d/*.fish $__extra_confdir/*.fish
set -l basename (string replace -r '^.*/' '' -- $file)
contains -- $basename $sourcelist
and continue
set sourcelist $sourcelist $basename
# Also skip non-files or unreadable files.
# This allows one to use e.g. symlinks to /dev/null to "mask" something (like in systemd).
[ -f $file -a -r $file ]
and source $file
end
What's going on here? How can I fix this?
What happens here is that a component of your $PATH, $fish_user_paths or a line in /etc/paths looks like an option.
Most likely, this is wrong, and you should remove it.
E.g. try printf '%s\n' $fish_user_paths. If that tells you that one of the entries is "-gx", then you've set it incorrectly and need to use set -e fish_user_paths[number-of-that-entry] to correct it.
Since these are all common options to set, you've probably once done something like set fish_user_paths /something -gx, which adds a "-gx" component (set only reads options before the variable name).
This has been reported upstream at https://github.com/fish-shell/fish-shell/issues/5662, and future fish versions won't spew an error, but the existence of the offending component is most likely an error, so you still want to remove it.
RHEL6
I have a c-shell script that runs a perl script. After dumping tons of stuff to stdout, it determines where (what dir) the parent shell should cd to when the perl script finishes. But that's a string, not an int which is all I can pass back with "exit()".
Storing the name of the dir in a file which the c-shell script can read is what I have now. It works, but is not elegant. Is there a better way to do this ? Maybe a little chunk of memory that I can share with the perl script ?
Short:
Redirect Perl's streams and restore in the end to print that info, taken by the shell script
Or, print that last and the shell script can pass output to the console and take the last line
Or, use a named pipe (either shell) or specific file descriptors (not csh) for that print
When the Perl script prints out that name you can assign it to a variable
in the shell script
#!/bin/csh
set DIR `perl -e'print "dir_name"'`
while in bash
#!/bin/bash
DIR="$(perl -e'print "dir_name"')"
where $(...) is preferred for the command substitution.
But those other prints to console from the Perl script then need be handled
One way is to redirect all output in Perl script other than that one print, what can be controlled by a command-line option (filename to which to redirect, which shell script can print out)
Or, take all Perl's output and pass it to console, the last line being the needed "return." This puts the burden on the Perl script to print that last (perhaps in an END block). The program's output can be printed from the shell script after it completes or line by line as it is emitted.
Or, use a named pipe (both shells) or a specific file descriptor (bash only) to which the Perl script can print that information. In this case its streams go straight to the console.
The question explicitly mentions csh so it is given below. But I must repeat the old and worn fact that shell scripting is far better done in bash than in csh. I strongly recommend to reconsider.
bash
If you need the program's output on the console as it goes, take and print it line by line
#!/bin/bash
while read line; do
echo "$line"
DIR=$line
done < <(perl script.pl)
echo "$DIR"
Or, if you don't need output on the console before the script is finished
#!/bin/bash
mapfile -t lines < <(perl script.pl)
DIR="${lines[-1]}"
printf '%s\n' "${lines[#]}" # print script.pl's output
Or, use file descriptors for that particular print
F=$(mktemp) # safe filename
exec 3> "$F" # open fd 3 to write to it
exec 4< "$F" # open fd 4 to read from it
rm -f "$F" # remove file(name) for safety; opened fd's can still access
perl -E'$fd=shift; say "...normal prints to STDOUT...";
open(FH, ">&=$fd") or die $!;
say FH "dirname";
close FH
' 3
read dir_name <&4
exec 3>&- # close them
exec 4<&-
echo "$dir_name"
I couldn't get it to work with a single file descriptor for both reading and writing (exec 3<> ...), I think because the read can't rewind after the write, thus separate descriptors are used.
With a Perl script (and not the demo one-liner above) pass the fd number as a command-line option. The script can then do this only if it's invoked with that option.
Or, use a named pipe very similarly to how it's done for csh below. This is probably best here, if the manipulation of the program's STDOUT isn't to your liking.
csh
Iterate over the program's (completed) output line by line
#!/bin/csh
foreach line ( "`perl script.pl`" )
echo "$line"
set dir_name = "$line"
end
echo "Directory name: $dir_name"
or extract the last line first and then print the whole output
#!/bin/csh
set lines = ( "`perl script.pl`" )
set dir_name = $lines[$#]
# Print program's output
while ( $#lines )
echo "$lines[1]"
shift lines
end
or use a named pipe
set fifo_name = "/tmp/fifo$$" # or use mktemp
mkfifo "$fifo_name"
( perl script.pl --fifo $fifo_name [other args] & )
set dir_name = `cat "$fifo_name"`
rm -f $fifo_name
echo "dir name from FIFO: $dir_name"
The Perl command is in the background since FIFO blocks until written and read. So if the shell script were to wait for perl ... to complete the Perl script would block as it's writing to FIFO (since that's not being read) so shell would never get to read it; we would deadlock. It is also in a subshell, with ( ), so to avoid the informational prints about the background job.
The --fifo NAME command-line option is needed so that Perl script knows what special file to use (and not to do this if the option is not there).
For an in-line example replace ( perl script ...) with this one-liner, used above as well
( perl -E'$ff = shift; say qq(\t...normal prints to STDOUT...);
open FF, ">$ff" or die $!;
say FF "dir_name_$$";
close FF
' $fifo_name
& )
(broken over lines for readability)
I want to pass text in as a variable rather than a file.
I am not sure how to explain this well only with an example.
I have a perl script with usage as follows printme.pl [file]
I want to run without passing in a file and just passing text.
echo print_me | perl printme.pl
rather than doing
perl printme.pl textfile.txt
I am trying to run a perl script that takes a text file as a variable and outputs using echo.
bash (amongst other shells) has a feature called process substitution. In this feature, you can add some shell code that outputs to stdout and have the shell treat it like a file.
In your case, you would write:
perl printme.pl <(echo "hello world")
Perl will receive in $ARGV[0] a filename that looks something like /dev/fd/63 from which it can read the line "hello world\n"
How can I launch the currently configured editor from the fish shell? That is the editor associated with $EDITOR.
What would a function look like that takes input from the pipeline and opens it in the editor identified by $EDITOR.
What would a function look like that opens a path in $EDITOR from the argument list?
How about something like:
function edit -d "Open a file using $EDITOR"
for file in $argv
if test -e $file
eval $EDITOR $file
echo "Opening file $file"
else
echo "Create file? (y/n)"
read createFile
if test $createFile = "y"
eval $EDITOR -n $file
echo "Creating file $file"
end
end
end
end
I would like to execute two or more commands back to back . But these commands are stored in a variable in my script. For example,
var="/usr/bin/ls ; pwd ; pooladm -d; pooladm -e"
The problem arises when I execute this variable via my script.
Suppose I go:
#!/bin/ksh -p
..
..
var="/usr/bin/ls ; pwd;pooladm -d; pooladm -e"
..
..
$var # DOES NOT WORK ..BUT WORKS WITH EVAL
It doesn't work ..
But the moment I use eval :
eval $var
It works brilliantly.
I was just wondering if there is any other way to execute a bunch of commands stored in a variable without using eval.
Also , Is eval usage considered a bad programming practice because my coding standards appear to shun its usage than embrace it . Please do let me know.
Remember that the shell only parses the line once. So when you expand your $var, it becomes one string containing blanks. Since you have no executable named '/usr/bin/ls ; pwd;pooladm -d; pooladm -e', it can't run it.
On the other hand, eval takes its arguments are re-scans them, now you get '/usr/bin/ls', 'pwd', and so on. It works.
eval is a little chancy because it leaves a possible security hole -- consider if someone managed to get 'rm -rf /' into the string. But it's a useful tool.
Use backticks and echo. In your case
`echo $var`
You could invoke another copy of the shell to run the command:
sh -c "$var"
This isn't necessarily better than using eval. The main practical difference is that eval will run the commands in the context of the current shell, while "sh -c" runs the commands in a separate shell instance. If var contains commands to set environment variables or change the current directory, you or may not want those commands to affect the current shell.