diff options
| author | cinap_lenrek <cinap_lenrek@gmx.de> | 2013-08-20 23:56:15 +0200 |
|---|---|---|
| committer | cinap_lenrek <cinap_lenrek@gmx.de> | 2013-08-20 23:56:15 +0200 |
| commit | 9a3a722ddeb73c7816bbbfa62f0d4accefdcae2b (patch) | |
| tree | e0759b70d684f7b754d0b60fe60146454b99479a /sys/src/cmd/rc | |
| parent | d8cd5d197de6756443c4a5aa109ff78656ebc200 (diff) | |
rc: flush environment variables (update /env) before fork
on races... normal forks will all share the /env environment but
not the in memory variables of rc. so when we would normally fork
whoever does an exec (flush) first will override what the values of the
/env variables are, *independent* of the variables that where
actually modified *in* the process.
when we flush *before* fork, then at least both processes start out
with marked clean in memory variables and the processes will flush
only the things they actually change.
Diffstat (limited to 'sys/src/cmd/rc')
| -rw-r--r-- | sys/src/cmd/rc/havefork.c | 9 |
1 files changed, 9 insertions, 0 deletions
diff --git a/sys/src/cmd/rc/havefork.c b/sys/src/cmd/rc/havefork.c index ea34acc3d..322ec0ce7 100644 --- a/sys/src/cmd/rc/havefork.c +++ b/sys/src/cmd/rc/havefork.c @@ -12,10 +12,12 @@ Xasync(void) int null = open("/dev/null", 0); int pid; char npid[10]; + if(null<0){ Xerror("Can't open /dev/null\n"); return; } + Updenv(); switch(pid = rfork(RFFDG|RFPROC|RFNOTEG)){ case -1: close(null); @@ -45,10 +47,12 @@ Xpipe(void) int lfd = p->code[pc++].i; int rfd = p->code[pc++].i; int pfd[2]; + if(pipe(pfd)<0){ Xerror("can't get pipe"); return; } + Updenv(); switch(forkid = fork()){ case -1: Xerror("try again"); @@ -91,6 +95,7 @@ Xbackq(void) Xerror("can't make pipe"); return; } + Updenv(); switch(pid = fork()){ case -1: Xerror("try again"); @@ -152,6 +157,7 @@ Xpipefd(void) char name[40]; int pfd[2]; int sidefd, mainfd; + if(pipe(pfd)<0){ Xerror("can't get pipe"); return; @@ -164,6 +170,7 @@ Xpipefd(void) sidefd = pfd[PRD]; mainfd = pfd[PWR]; } + Updenv(); switch(pid = fork()){ case -1: Xerror("try again"); @@ -191,6 +198,8 @@ void Xsubshell(void) { int pid; + + Updenv(); switch(pid = fork()){ case -1: Xerror("try again"); |