1 Various bits of what is known about busybox shells, in no particular order.
4 hush: '( echo ${name )' will show syntax error message, but prompt
5 doesn't return (need to press <enter>). Pressing Ctrl-C, <enter>,
6 '( echo ${name )' again, Ctrl-C segfaults.
9 hush: environment cannot be handled by libc routines as they are leaky
10 (by API design and thus unfixable): hush will leak memory in this script,
15 t=111111111111111111111111111111111111111111111111111111111111111111111111
17 ps -o vsz,pid,comm | grep " $pid "
19 The fix is to not use setenv/putenv/unsetenv but manipulate env ourself. TODO.
20 hush: meanwhile, first three command subst bugs mentioned below are fixed. :)
23 hush: more bugs spotted. Comparison with bash:
24 bash-3.2# echo "TEST`date;echo;echo`BEST"
25 TESTSun May 6 09:21:05 CEST 2007BEST [we dont strip eols]
26 bash-3.2# echo "TEST`echo '$(echo ZZ)'`BEST"
27 TEST$(echo ZZ)BEST [we execute inner echo]
28 bash-3.2# echo "TEST`echo "'"`BEST"
29 TEST'BEST [we totally mess up this one]
30 bash-3.2# echo `sleep 5`
31 [Ctrl-C should work, Ctrl-Z should do nothing][we totally mess up this one]
32 bash-3.2# if true; then
34 bash-3.2# [we re-issue "> "]
35 bash-3.2# if echo `sleep 5`; then
36 > true; fi [we execute sleep before "> "]
39 hush: made ctrl-Z/C work correctly for "while true; do true; done"
40 (namely, it backgrounds/interrupts entire "while")
43 hush: new bug spotted: Ctrl-C on "while true; do true; done" doesn't
45 # while true; do true; done
46 [1] 0 true <-- pressing Ctrl-C several times...
52 hush: update on "sleep 1 | exit 3; echo $?" bug.
53 parse_stream_outer() repeatedly calls parse_stream().
54 parse_stream() is now fixed to stop on ';' in this example,
55 fixing it (parse_stream_outer() will call parse_stream() 1st time,
56 execute the parse tree, call parse_stream() 2nd time and execute the tree).
57 But it's not the end of story.
58 In more complex situations we _must_ parse way farther before executing.
59 Example #2: "{ sleep 1 | exit 3; echo $?; ...few_lines... } >file".
60 Because of redirection, we cannot execute 1st pipe before we parse it all.
61 We probably need to learn to store $var expressions in parse tree.
62 Debug printing of parse tree would be nice too.
65 hush: Ctrl-C and Ctrl-Z for single NOFORK commands are working.
66 Memory and other resource leaks (opendir) are not addressed
67 (testcase is "rm -i" interrupted by ctrl-c).
70 hush: "sleep 5 | sleep 6" + Ctrl-Z + fg seems to work.
71 "rm -i" + Ctrl-C, "sleep 5" + Ctrl-Z still doesn't work
72 for SH_STANDALONE case :(
75 hush: fixed non-backgrounding of "sleep 1 &" and totally broken
76 "sleep 1 | sleep 2 &". Noticed a bug where successive jobs
77 get numbers 1,2,3 even when job #1 has exited before job# 2 is started.
78 (bash reuses #1 in this case)
81 hush: "sleep 1 | exit 3; echo $?" prints 0 because $? is substituted
82 _before_ pipe gets executed!! run_list_real() already has "pipe;echo"
83 parsed and handed to it for execution, so it sees "pipe"; "echo 0".
86 hush: removed setsid() and made job control sort-of-sometimes-work.
87 Ctrl-C in "rm -i" works now except for SH_STANDALONE case.
88 "sleep 1 | exit 3" + "echo $?" works, "sleep 1 | exit 3; echo $?"
89 shows exitcode 0 (should be 3). "sleep 1 | sleep 2 &" fails horribly.
92 lash, hush: both do setsid() and as a result don't have ctty!
93 Ctrl-C doesn't work for any child (try rm -i), etc...
94 lash: bare ">file" doesn't create a file (hush works)