1 1.11 rillig # $NetBSD: varmod-assign-shell.mk,v 1.11 2025/01/11 21:21:33 rillig Exp $ 2 1.1 rillig # 3 1.1 rillig # Tests for the variable modifier '::!=', which assigns the output of a shell 4 1.1 rillig # command to the variable, but only if the command exited successfully. This 5 1.3 rillig # is different from the other places that capture the output of an external 6 1.3 rillig # command (variable assignment operator '!=', expression modifier ':sh', 7 1.3 rillig # expression modifier ':!...!'), which also use the output when the shell 8 1.3 rillig # command fails or crashes. 9 1.1 rillig # 10 1.1 rillig # The variable modifier '::!=' and its close relatives have been around since 11 1.1 rillig # var.c 1.45 from 2000-06-01. 12 1.1 rillig # 13 1.1 rillig # Before 2020.08.25.21.16.53, the variable modifier '::!=' had a bug for 14 1.1 rillig # unsuccessful commands, it put the previous value of the variable into the 15 1.1 rillig # error message instead of the command that was executed. That's where the 16 1.1 rillig # counterintuitive error message 'make: "previous" returned non-zero status' 17 1.1 rillig # comes from. 18 1.1 rillig 19 1.2 rillig DIRECT= previous 20 1.6 rillig # expect+1: warning: Command "echo output; (exit 13)" exited with status 13 21 1.6 rillig DIRECT!= echo output; (exit 13) 22 1.1 rillig 23 1.2 rillig ASSIGNED= previous 24 1.7 rillig .MAKEFLAGS: -dv # to see the "Capturing" debug output 25 1.9 rillig # expect+1: warning: Command "echo output; (exit 13)" exited with status 13 26 1.6 rillig _:= ${ASSIGNED::!=echo output; ${:U(exit 13)}} 27 1.4 rillig .MAKEFLAGS: -d0 28 1.1 rillig 29 1.1 rillig all: 30 1.1 rillig @echo DIRECT=${DIRECT:Q} 31 1.1 rillig @echo ASSIGNED=${ASSIGNED:Q} 32
Indexes created Sat Sep 20 22:09:52 GMT 2025