libremessages(1) -- common Bash routines
========================================
## SYNOPSIS
`. "$(librelib messages)"`
`. libremessages`
`libremessages`
## DESCRIPTION
`libremessages` is a shell library containing many common routines.
The name is a bit of a misnomer, it mostly deals with printing
messages, but also has other things.
`libremessages` uses `common.sh`(3) internally for a large portion of
it's functionality. The authors make no promises that functionality
that is implemented in `libremessages` won't move into `common.sh` or
vice-versa. So, it is recommended that you use `libremessages`, not
`common.sh`.
### STAND ALONE USAGE
The "normal" way to use libremessages is to source it, then call the
provided routines.
However, if you call libremessages directly, the first argument is
taken as the function to call, and the remaining arguments are passed
to it. The only cases where this doesn't work are the lockfile
routines (`lock`, `slock`, and `lock_close`), because lockfiles are
managed as file descriptors.
### VARIABLES
The following variables for printing terminal color codes are set:
`ALL_OFF`, `BOLD`, `BLUE`, `GREEN`, `RED`, `YELLOW`. If standard
error is not a terminal (see `isatty`(3)), they are set, but empty.
They are marked as readonly, so it is an error to try to set them
afterwords.
### MESSAGE FORMAT
All routines feed the message/format string through `gettext`(1), if
it is available.
The descriptions will frequently reference `printf`(1)--this isn't
really that `printf`. The program described by the manual page
`printf`(1) is probably the version from GNU coreutils, every time it
is used here, it is `bash`(1)'s internal implementation; try running
the command `help printf` from a Bash shell for more information.
### GENERAL ROUTINES
Unless otherwise noted, these do not implicitly call `gettext`.
* `_` :
If `gettext` is available, calls `gettext`, otherwise just prints
the arguments given.
* `in_array` ...:
Evaluates whether includes ; returns 0 if it
does, non-zero if it doesn't.
* `panic`:
For the times when you can't reasonably continue, similar to
"assert" in some programming languages.
* `setup_traps` []:
Sets traps on TERM, HUP, QUIT and INT signals, as sell as the ERR
event, similar to makepkg. If is specified, instead of
using the default handler (which is good for most purposes), it
will call with the arguments
` [...]`, where
is a `printf`(1)-formatted string that is fed through
`gettext`, and are its arguments.
* `whitespace_collapse`:
Collapses whitespace on stadard I/O, similar to HTML whitespace
collapsing, with the exception that it puts two spaces between
sentences. It considers newline, tab, and space to be
whitespace.
### PROSE ROUTINES
These routines print to standard output, and are useful for printing
word-wrapped prose.
For each of these, is fed through `gettext` automatically.
* `prose` [...]:
Takes a `printf`(1)-formatted string, collapses whitespace
(HTML-style), and then word-wraps it.
* `bullet` [...]:
Similar to `prose`, but prints a bullet point before the first
line, and indents the remaining lines.
* `flag` [ ...]:
Print a flag and description formatted for `--help` text. For
example:
`flag '-N' 'Disable networking in the chroot'`
The description is fed through `gettext`, the flag is not, so if
part of the flag needs to be translated, you must do that
yourself:
`flag "-C <$(_ FILE)>" 'Use this file instead of pacman.conf'`
Newlines in the description are ignored; it is
whitespace-collapsed (so newlines are stripped), then it is
re-word-wrapped, in the same way as `prose` and `bullet`. If you
pass in multiple flag/description pairs to the same invocation,
the descriptions are all aligned together.
### NOTIFICATION ROUTINES
These routines print to standard error, and all take arguments in the
same format as `printf`(1), except for `stat_done`, which doesn't take
any arguments. Each of these print to stderr, not stdout.
For each of these, is fed through `gettext` automatically.
* `plain` [...]:
Prints a "plain" message in bold, indented with 4 spaces.
* `msg` [...]:
Prints a top-level priority notification.
* `msg2` [...]:
Prints a secondary notification.
* `warning` [...]:
Prints a warning.
* `error` [...]:
Prints an error message.
* `stat_busy` [...]:
Prints a "working..." type message without a trailing newline.
* `stat_done`:
Prints a "done" type message to terminate `stat_busy`.
* `print` [...]:
Like `printf`(1), but `gettext`-aware, and automatically prints a
trailing newline.
* `term_title` [...]:
Sets the terminal title to the specified message.
### TEMPORARY DIRECTORY MANAGEMENT
These are used by devtools, and not used within the rest of
libretools.
They work by creating and removing the directory referred to by the
variable $; `libretools.conf`(5) uses the same variable to
where the user saves all their work. If you aren't careful with
these, you could end up deleting a lot of someone's work.
* `setup_workdir`:
Creates a temporary directory, and sets the environmental
variable $ to it. Also sets traps for the signals INT,
QUIT, TERM and HUP to run `abort`; and EXIT to run `cleanup`
(see `signal`(7)).
* `cleanup` []:
*If* `setup_workdir` has been run, `rm -rf "$WORKDIR"`. If given
a numeric argument, it will then call `exit`(1) with that
argument, otherwise it calls `exit`(1) with a status of 0.
* `abort`:
Calls `msg` with the message "Aborting...", then calls
`cleanup 255`.
* `die` [...]:
Exactly like `error`, but calls `cleanup` and calls `exit`(1)
with a status of 255.
### LOCKFILE ROUTINES
* `lock` [...]:
Opens (creating if necessary) the file with file
descriptor in the current process, and gets an exclusive
lock on it. If another program already has a lock on the file,
and this program needs to wait for the lock to be released, then
it uses `stat_busy`/`stat_done` to print .
* `slock` [...]:
Identical like `lock`, but opens a shared lock. This is also
known as a "read lock". Many programs can have a shared lock at
the same time, as long as no one has an exclusive lock on it.
* `lock_close` :
Closes file descriptor , releasing the lock opened on it.
### MAKEPKG ROUTINES
These routines relate to `makepkg`(8).
* `find_cached_package` [-:
Searches for a locally built copy of the specified package, in
and the current working directory. If is not
specified, any value will match. If multiple matching files are
found (not counting duplicate links), then an error is printed to
stderr and nothing is printed to stdout.
* `get_full_version` []:
Inspects variables that are set, and prints the full version
spec, including if necessary, , and . By
default, it will print the information for , following
the normal rules for finding . If is given,
it will print the information for that sub-package. The versions
for different parts of a split package don't have to be the same!
## BUGS
Generating `.pot` files for the prose functions is a pain. The
libretools Makefiles have rules to do it, but it might make sense to
pull it into a separate program.
`term_title` currently only knows about the terminals screen, tmux,
xterm and rxvt (and their various values;
"rxvt-unicode-256color" is still rxvt).
## SEE ALSO
librelib(7), gettext(1), common.sh(3)
Things that were mentioned:
bash(1), exit(1), isatty(3), libretools.conf(5), makepkg(8),
printf(1), signal(7)