shtk_cli_usage_error.3

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.Dd July 11, 2017
.Dt SHTK_CLI_USAGE_ERROR 3
.Os
.Sh NAME
.Nm shtk_cli_usage_error
.Nd Prints a usage error and exits
.Sh LIBRARY
shtk_import cli
.Sh SYNOPSIS
.Nm shtk_cli_usage_error
.Ar message1
.Op Ar .. messageN
.Sh DESCRIPTION
The
.Nm
function prints the given usage error message to stderr and terminates
execution of the script with a return value of 1.
The message can be provided as one or more arguments as depicted by
.Ar message1
to
.Ar messageN ;
all arguments are concatenated together into a single line.
.Pp
The printed message has the following form, where
.Sq progname
is determined by
.Xr shtk_cli_progname 3 :
.Bd -literal -offset indent
progname: E: message1 .. messageN
Type 'man progname' for help.
.Ed
.Pp
.Nm
should be used to inform the user of problems directly caused by his invocation
of the script (e.g. the use of an invalid flag).
.Pp
By default, the printed error message refers to a manual page for the script.
You should have one, but if you don't, you can use the
.Xr shtk_cli_set_help_command 3
function early on in your script to customize the command shown to the user.
.Sh SEE ALSO
.Xr shtk 3 ,
.Xr shtk_cli 3 ,
.Xr shtk_cli_set_help_command 3
.Sh HISTORY
.Nm
first appeared in
.Nm shtk
1.0.