54 lines
2.3 KiB
Plaintext
54 lines
2.3 KiB
Plaintext
|
Warning:
|
||
|
|
|
||
|
|
This code must corrctly handle lots of picky little details to meet
|
||
|
|
the Unix98 standard while simultaneously being as compatible as
|
||
|
|
possible with the original Linux ps. Don't "fix" something without
|
||
|
|
considering the impact on all the special-case code. For example,
|
||
|
|
the "tty" format _must_ use "TT" as the header, even though the SysV
|
||
|
|
output formats _must_ use "TTY".
|
||
|
|
|
||
|
|
File overview:
|
||
|
|
|
||
|
|
display.c main(), debug code, iterates over processes
|
||
|
|
escape.c Does stuff like \202 and < to command and environment.
|
||
|
|
global.c Data + code to init it.
|
||
|
|
help.c Help message.
|
||
|
|
output.c Giant tables and lots of output functions.
|
||
|
|
parser.c Initial command parsing.
|
||
|
|
select.c want_this_proc() checks a process against flags & lists
|
||
|
|
sortformat.c Parses sort & format specifier lists. Picks output format.
|
||
|
|
stacktrace.c Debug code, not normally used.
|
||
|
|
../proc/* Library used to gather data.
|
||
|
|
regression Regression tests that ought to be run.
|
||
|
|
common.h Lots of interesting stuff.
|
||
|
|
Makefile Makefile
|
||
|
|
p Script used to test ps when the library is not installed.
|
||
|
|
utf Empty file used to test "ps ut?" unmangling behavior.
|
||
|
|
ps.1 Man page.
|
||
|
|
|
||
|
|
Compiling:
|
||
|
|
|
||
|
|
Whatever you do, don't trust the Makefiles. They are severely broken.
|
||
|
|
You can touch top.h and top won't be recompiled, or you can change
|
||
|
|
library files and discover that the library and programs won't be
|
||
|
|
recompiled.
|
||
|
|
|
||
|
|
Operation:
|
||
|
|
|
||
|
|
Unless the personality forces BSD parsing, parser.c tries to parse the
|
||
|
|
command line as a mixed BSD+SysV+Gnu mess. On failure, BSD parsing is
|
||
|
|
attempted. If BSD parsing fails _after_ SysV parsing has been attempted,
|
||
|
|
the error message comes from the original SysV parse.
|
||
|
|
|
||
|
|
Control goes to sortformat.c, which must pick apart ambiguous options
|
||
|
|
like "O". Failure can reset the whole program and set PER_FORCE_BSD,
|
||
|
|
which means a second trip through parser.c and sortformat.c.
|
||
|
|
|
||
|
|
The choice of output format happens in sortformat.c. There is a switch()
|
||
|
|
with all the valid format_flags combinations. The SysV and default
|
||
|
|
options are NULL (unless overridden by personality), which causes a
|
||
|
|
trip through SysV output format generation hackery. Note that the
|
||
|
|
default format always goes through there, even if it is for BSD.
|
||
|
|
Formats that came from the switch() (generally BSD, plus overrides)
|
||
|
|
get mangled a bit to support various SysV output modifiers.
|