diff options
Diffstat (limited to 'contrib/bmake/bmake.1')
| -rw-r--r-- | contrib/bmake/bmake.1 | 70 |
1 files changed, 46 insertions, 24 deletions
diff --git a/contrib/bmake/bmake.1 b/contrib/bmake/bmake.1 index d7ed08af0c07..82cec21dca4a 100644 --- a/contrib/bmake/bmake.1 +++ b/contrib/bmake/bmake.1 @@ -1,4 +1,4 @@ -.\" $NetBSD: make.1,v 1.209 2012/10/08 15:09:48 christos Exp $ +.\" $NetBSD: make.1,v 1.210 2013/01/27 18:52:01 sjg Exp $ .\" .\" Copyright (c) 1990, 1993 .\" The Regents of the University of California. All rights reserved. @@ -29,7 +29,7 @@ .\" .\" from: @(#)make.1 8.4 (Berkeley) 3/19/94 .\" -.Dd October 8, 2012 +.Dd January 23, 2013 .Dt MAKE 1 .Os .Sh NAME @@ -468,6 +468,50 @@ except that the effect can be limited to a single line of a script. A .Ql Ic \- causes any non-zero exit status of the command line to be ignored. +.Pp +When +.Nm +is run in jobs mode with +.Fl j Ar max_jobs , +the entire script for the target is fed to a +single instance of the shell. +.Pp +In compatibility (non-jobs) mode, each command is run in a separate process. +If the command contains any shell meta characters +.Pq Ql #=|^(){};&<>*?[]:$`\e\en +it will be passed to the shell, otherwise +.Nm +will attempt direct execution. +.Pp +Since +.Nm +will +.Xr chdir 2 +to +.Ql Va .OBJDIR +before executing any targets, each child process +starts with that as its current working directory. +.Pp +Makefiles should be written so that the mode of +.Nm +operation does not change their behavior. +For example, any command which needs to use +.Dq cd +or +.Dq chdir , +without side-effect should be put in parenthesis: +.Bd -literal -offset indent + +avoid-chdir-side-effects: + @echo Building $@ in `pwd` + @(cd ${.CURDIR} && ${.MAKE} $@) + @echo Back in `pwd` + +ensure-one-shell-regardless-of-mode: + @echo Building $@ in `pwd`; \\ + (cd ${.CURDIR} && ${.MAKE} $@); \\ + echo Back in `pwd` +.Ed .Sh VARIABLE ASSIGNMENTS Variables in make are much like variables in the shell, and, by tradition, consist of all upper-case letters. @@ -2027,28 +2071,6 @@ NetBSD 5.0 so that they still appear to be variable expansions. In particular this stops them being treated as syntax, and removes some obscure problems using them in .if statements. -.Pp -Unlike other -.Nm -programs, this implementation by default executes all commands for a given -target using a single shell invocation. -This is done for both efficiency and to simplify error handling in remote -command invocations. -Typically this is transparent to the user, unless the target commands change -the current working directory using -.Dq cd -or -.Dq chdir . -To be compatible with Makefiles that do this, one can use -.Fl B -to disable this behavior. -.Pp -In compatibility mode, each command is run in a separate process. -If the command contains any shell meta characters -.Pq Ql #=|^(){};&<>*?[]:$`\e\en -it will be passed to the shell, otherwise -.Nm -will attempt direct execution. .Sh SEE ALSO .Xr mkdep 1 .Sh HISTORY |