Mailing-List: contact cygwin-developers-help AT sourceware DOT cygnus DOT com; run by ezmlm
List-Unsubscribe: <mailto:cygwin-developers-unsubscribe-archive-cygwin-developers=delorie DOT com AT sourceware DOT cygnus DOT com>
List-Subscribe: <mailto:cygwin-developers-subscribe AT sourceware DOT cygnus DOT com>
List-Archive: <http://sourceware.cygnus.com/ml/cygwin-developers/>
List-Post: <mailto:cygwin-developers AT sourceware DOT cygnus DOT com>
List-Help: <mailto:cygwin-developers-help AT sourceware DOT cygnus DOT com>,
	<http://sourceware.cygnus.com/ml/#faqs>
Sender: cygwin-developers-owner AT sourceware DOT cygnus DOT com
Delivered-To: mailing list cygwin-developers AT sourceware DOT cygnus DOT com
Date: Wed, 25 Aug 1999 13:19:59 +0400
From: Egor Duda <deo AT logos-m DOT ru>
X-Mailer: The Bat! (v1.029) S/N A0F2A05A
Reply-To: Egor Duda <deo AT logos-m DOT ru>
Organization: DEO
Message-ID: <9555.990825@logos-m.ru>
To: cygwin-developers <cygwin-developers AT sourceware DOT cygnus DOT com>
Subject: strace attaching to already running process
Mime-Version: 1.0
Content-Type: multipart/mixed; boundary="----------33104228565668"

------------33104228565668
Content-Type: text/plain; charset=us-ascii
Content-Transfer-Encoding: 7bit

Hi!

  I needed some debugging info from ever-running cygwin daemon, so i've
patched strace a bit to allow it to attach to already running process.
Suppling windows pid of process in a form

strace -o <file> -p <winpid>

will do the job. There's two drawbacks, however, both due to features
of DebugActiveProcess API. First -- when strace exits, debugee exits
too. And second -- '-f' option don't work. Working around second
limitation seems possible, but solution i see is quite ugly -- it
suppose that when debugee starts child processes through fork or
spawn, it'll pass DEBUG_PROCESS flag to CreateProcess, and redirect
all children's debug output to actual strace. But it will require that
debugee must stay alive as long as children are running, so, a bunch of
additional syncronization is needed. Anyway, stracing single running
process seems to work ok.

Egor.            mailto:deo AT logos-m DOT ru ICQ 5165414 FidoNet 2:5020/496.19
------------33104228565668
Content-Type: application/x-gzip; name="strace_by_pid.diff.gz"
Content-Transfer-Encoding: X-UUE
Content-Disposition: attachment; filename="strace_by_pid.diff.gz"

filetime 655977088
begin 644 strace_by_pid.diff.gz
M'XL("`+<NC<``W-T<F%C95]B>5]P:60N9&EF9@#-6&U3VT AT 2_@R_HN,KP"^R
MD2P9C+U)%0D.RQ:!JX14[BJ[ZY*EL:5%EE2:,5XVQ7^_[IG1BVV1NZNDMN(/
M(&MZ>OKEZ:=[[(?S.70]&[H9K,.8K])C'B[2+/%ZGJ??]*S*N_UVN[TKN7<7
MK.!\M0"K#Y8S,H>C_ AT E89V=G^]UNMT[-WB?FJPU#L,R1/1S13MK0WOS(\ZR!
MT3=!?B5]]-4"?.KN`_PCC+UHY3/XB3_RX[4;BE[P:N,]R[(XV7[)A1^%,WK;
MV7P;;HLVM/E!8T/!THTB=$7*UAH]-(WAH#1Z:!G#86[T!^&*T(.?SV\NKB>`
M8?&291HQP:9Q$B_=,(:7<//Q^GI\?`P?V-)-@R1CD+DAQ[#-DPQ0K$MRJ&N/
M/B@'(LB8ZW-8!RP&E[3&;@2!RV$>QB$/F%^5ID0PSL-X AT 1'8L8>+S/58;H7<
M,7E AT L8`TX0)MD&=H(=2TR-PEJLF5K]U8<!`)N$*X7K#C<$!IFN(Q&P?\[,9^
MQ""90[&L7'IN_VI&3A0Z-E3@[D*@T%(/+MOL&Y9MV16`V>8`7R'F=+[PTT;7
MY(-.59C$>J$V?P!=X$7F5"ZV<J?M AT B36Z\\?U"D.DB&7`EU AT SV5D*_[TM.):
M^['\3R:[P AT O07OX84PP73*"]T*18&M#(!1H&F`:\.__7]>W-96N\O3D'ZQOT
M1+`2JLU#SCQ:QXB$056'(;.UK>G;U>P6T'=0MJ%)%<"VEKOW'R<&O#V__C`I
MU%"ZO,#-RDJ:REQ-8W?)/@_,WT#)\#0+8S&'9IT<)L%[7"#Y]-123R[U#B*_
M`09<,O%FE67XYI^JD*]\:+:@E6NNE/#7K-=VZW]U9D`9%BJF:6YR8P<%!VG#
MV,&&W"T5'+>1RH1`P@%_71H]C]P%8C5P!?X)><Y+@(]QL@;/3=V9*NF,>2Q\
M(,*J+^.^0S5[5BUCV\)7]FE9QGBN8)[0/-'<P)]VM$9D"UO_75!+=6JE5(@W
M`G.%G,>.'AC,&%8Q^Q,]]0V,!R.28(A=C`878101KXO5#"(V%R`IA/B7/81)
M4>#4;OUD74:2R)*BCBS`&:J:0RB.2)^;$7&XH&!6R$N*$KUGHNR8&-*![L9T
M("958RNG[2FV&]1<`D>$/N*PA.R=)#Z)6!F%%RBFJ5VF AT RT__X8;OFRD9Q=;
MQC:-/3T#U?=XVF,/2MRA/0<^HG7YR%DT[[ZJ`%);343='(];*JCP1=I(GXM/
MM^\O("/*_(3^ODVR=ZM(A)CWV]D?F&@.3=O(W:A6UC1*DG1*,2I3K].?&RQ8
MM AT QC+%9,%"K:V$3I^XME"?W'!(<>B5'9%(HP];*"=%OA0;**?"AT]G1-.$-*
MX+"LB1\H AT 14*^D%RZ?R AT N:POSL$9YO;$J5+@R2F^.CW+T[WW5+477>^B[^=7
M=]/;U[],WMQ-3<5:]$&B:%)LM AT 2@`W:K$)+QK'P!/8-,74^$#]1^+!AO"3SB
MP+*L-!+5J-2LPOQ&:TO>2V+DKQ7;U/.$7PH_4!/X(4]EI AT BJ,E7C8IV':7F>
MNW;O6:,UKF;MO$!B96JCT5D2<CZ^(>P^>*YB7:J*Q$_V_=T;U`J9FA_KKEV]
M1FTM5.]26TO%A<H<@'4R,NV1Z=1<J+9W56]5UJA/%ZNOW*JP.9Y4H()?BT[)
MU;R-H>="C3+M=+$<ERL4<:RK>Y_-5C3&FUMK AT OV):,VP\N1:)U]3)9=*/C%U
M[>BEU[>WU^!%"6?30'?+?-XW]+[D7M5;G3NV91HVW AT MU8Y+9Q:3%GZ]N[M[?
M7D]NB)&.?C6/5.()W2^(3#1;O&/+)'N$9N`%883--S7D;@/R[08<QK-'P7BK
MM=_%B^`\]MD<+B:O/UY>7MU<:C1E3*RR>$P2+.(,_]-'1:)ITDQ'E1P?"1JX
M88D'NPN&[3Q>B`#F6;($?6NA3GS AT _W20OC**CJ[4$-NA7KH#A&AH;C"R\[7+
MQ40=U6HI&Y!=YGDTR&7$2NPM4V AT JYQK>OQ?(G7:KM6T_(L)&2- AT Y)NI"[EA#
MP^F?Y"%_VDCG0Q+2G<M/='TW5S'5$2)TZ?)[9-,KS&P[F8<1CKH*8FTW6SR0
M)8JB/3FX3J5_:#"MJ=Q)@M6OE3*IIN3BJA>.Y1B.71!@C9$=S3U3D4SST#<+
MH!+7??D[1GHJBGQ^K[F);XSQZI;VOTWO'9UZ>%&JRPF\`DSUF*0LIF%1RTE-
M1 AT 5X&S"3*"O5PP61P;DD?EU530K@\Z>IN.OAM$#]:N/`-/2_>FHYOE3"]94S
M.=4$GJANS___N;+Q=+X?RLD+"3,UE>Q`42Z.Y:ID%"7V[;516]`V%K3CE,.]
M/%$Q`_)_IU-,>VL\`;UM)JE0/Q[0`]F!,QQ9@^%>CI+17#1:+7CQ$B:W;W.*
MX>N0^BQMS5]1+(IV[W(&1_.CD:K>@64X@\H-[ELM2K_-IMJH#4X-YZ1?ME+G
MU#2<T\J(7>H0J`.GL+(]_HX3$OFP-\.,WI<CCA)/4;P#>ZI?(L0$=@]I)7JD
M?FXPP#(E+G,%^7G%H"<['4&A56_]Z8GA#*TRYQ(\TRC$SM_V*A,TC<F'<A&O
M`&/UW>N^BM$5&4[Y*QSDX:-3<350/]&]A``.#TD</4%9;.3%%%ZIT#?8_:DV
M%7[U%"!_5P AT TO!5Z AT 019?J=6:T\J]&=]PSFKX.7O]F;MHGG?P9G_`"1,#[::
#%P``
`
end
filesize 2028
------------33104228565668--