1 # $NetBSD: varmod-exclam-shell.mk,v 1.4 2020/11/03 18:42:33 rillig Exp $
3 # Tests for the :!cmd! variable modifier, which evaluates the modifier
4 # argument, independent of the value or the name of the original variable.
6 .if ${:!echo hello | tr 'l' 'l'!} != "hello"
10 # The output is truncated at the first null byte.
11 # Cmd_Exec returns only a string pointer without length information.
12 # Truncating the output is not necessarily intended but may also be a side
13 # effect from the implementation. Having null bytes in the output of a
14 # shell command is so unusual that it doesn't matter in practice.
15 .if ${:!echo hello | tr 'l' '\0'!} != "he"
19 # The newline at the end of the output is stripped.
24 # Only the final newline of the output is stripped. All other newlines are
25 # converted to spaces.
26 .if ${:!echo;echo!} != " "
30 # Each newline in the output is converted to a space, except for the newline
31 # at the end of the output, which is stripped.
32 .if ${:!echo;echo;echo;echo!} != " "