shtk.3

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.Dd January 6, 2025
.Dt SHTK 3
.Os
.Sh NAME
.Nm shtk
.Nd Application Programming Interface (API) of the Shell Toolkit
.Sh DESCRIPTION
The Shell Toolkit, or
.Nm
for short, is a collection of modules written in
.Xr sh 1
that provide common functionality to simplify the implementation of complex
shell scripts.
This page provides an introduction to writing scripts using
.Nm
and serves as a reference to all the provided modules by it.
.Ss Script structure
Scripts using
.Nm
follow this structure:
.Bd -literal -offset indent
shtk_import module1
shtk_import moduleN

# possibly define globals here

some_custom_function() {
    local arg1="${1}"; shift
    local arg2="${1}"; shift

    # do something
}

main() {
    # program entry point; automatically invoked
}
.Ed
.Pp
In particular, note: that there is no shebang line at the beginning of the
script; that there is no explicit call to
.Nm main ;
and that there is no code outside of shell functions other than for calls to
.Xr shtk_import 3 .
.Ss Script compilation
The
.Xr shtk 1
tool offers a compilation process for scripts using
.Xr shtk 3 .
In this context, compilation just refers to the addition of initialization
boilerplate code to the script so that the correct modules can be located and
that a well-known shell interpreter is used.
.Ss Modules
The
.Xr shtk_import 3
function depicted above is used to bring the specified modules into the script.
For details on all existing modules, see the list of cross-referenced pages
in the
.Sx SEE ALSO
section below.
.Sh SEE ALSO
.Xr shtk 1
.Ss Built-in functions
.Xr shtk_abort 3 ,
.Xr shtk_import 3
.Ss Modules
.Xr shtk_bool 3 ,
.Xr shtk_cleanup 3 ,
.Xr shtk_cli 3 ,
.Xr shtk_config 3 ,
.Xr shtk_cvs 3 ,
.Xr shtk_fs 3 ,
.Xr shtk_git 3 ,
.Xr shtk_hw 3 ,
.Xr shtk_list 3 ,
.Xr shtk_process 3 ,
.Xr shtk_unittest 3 ,
.Xr shtk_version 3
.Sh AUTHORS
The
.Nm
package was developed by
.An Julio Merino
.Aq jmmv@google.com .