Right, strace is generally not so useful. ltrace is often a bit better (since it enables libc call tracing too). gdb is the best naturally. Does anyone know of a call tracing app that uses ptrace to trace in-program system calls btw?

/ David Hedbor

Previous text:

2003-02-12 23:05: Subject: Re: Weird problem with Image.SVG in Pike 7.4/7.5

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On Wed, Feb 12, 2003 at 10:40:06PM +0100, David Hedbor @ Pike developers forum scribbled:

...

Again, gdb/strace output would be good. That way there would be a way to see where it actually dies.

Output from strace:

5506 [4000d134] read(12,"\177ELF\1\1\1\0\0\0\0\0\0\0\0\0\3\0\3\0\1\0\0\0\210!\0"..., 1024) = 1024 5506 [4000cf1f] fstat64(12, {st_dev=makedev(3, 7), st_ino=41979580,st_mode=S_IFREG|0644, st_nlink=1, st_uid=0, st_gid=0, st_blksize=4096, st_blocks=240, st_size=122740, st_atime=2003/02/12-22:56:01, st_mtime=2003/02/03-01:25:35, st_ctime=2003/02/03-23:27:05}) = 0 5506 [4000d5bd] old_mmap(NULL, 121648, PROT_READ|PROT_EXEC, MAP_PRIVATE, 12, 0) = 0x4084b000 5506 [4000d644] mprotect(0x40865000, 15152, PROT_NONE) = 0 5506 [4000d5bd] old_mmap(0x40865000, 16384, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED, 12, 0x1a000) = 0x40865000 5506 [4000d0ed] close(12) = 0 5506 [4000d601] munmap(0x405ee000, 60619) = 0 5506 [4016c3b1] gettimeofday({1045086961, 185815}, NULL) = 0 5506 [080c25ab] --- SIGINT (Interrupt) @ 0 (0) --- 5506 [4019d944] write(9, "\2", 1) = 1 5506 [4010c8a0] sigreturn() = ? (mask now [RTMIN])

SIGINT is where I press Ctrl-C - it gets caught somewhere and process doesn't exit. As you see, not much there...

And the output from stracing the "healthy" pike:

5591 [4000d0b4] open(0x40622be8, O_RDONLY) = 12 5591 [4000d134] read(12,"\177ELF\1\1\1\0\0\0\0\0\0\0\0\0\3\0\3\0\1\0\0\0\210!\0"..., 1024) = 1024 5591 [4000cf1f] fstat64(12, {st_dev=makedev(3, 7), st_ino=41979580,st_mode=S_IFREG|0644, st_nlink=1, st_uid=0, st_gid=0, st_blksize=4096, st_blocks=240, st _size=122740, st_atime=2003/02/12-23:00:24, st_mtime=2003/02/03-01:25:35,st_ctime=2003/02/03-23:27:05}) = 0 5591 [4000d5bd] old_mmap(NULL, 121648, PROT_READ|PROT_EXEC, MAP_PRIVATE, 12, 0) = 0x40873000 5591 [4000d644] mprotect(0x4088d000, 15152, PROT_NONE) = 0 5591 [4000d5bd] old_mmap(0x4088d000, 16384, PROT_READ|PROT_WRITE,MAP_PRIVATE|MAP_FIXED, 12, 0x1a000) = 0x4088d000 5591 [4000d0ed] close(12) = 0 5591 [4000d601] munmap(0x40616000, 60619) = 0 5591 [4016d3b1] gettimeofday({1045087224, 28059}, NULL) = 0 5591 [401a76a4] mprotect(0x83b5558, 0, PROT_READ|PROT_WRITE|PROT_EXEC) = -1 EINVAL (Invalid argument) 5591 [4016d3b1] gettimeofday({1045087224, 28822}, NULL) = 0 5591 [401a76a4] mprotect(0x83a51b0, 104, PROT_READ|PROT_WRITE|PROT_EXEC) = -1 EINVAL (Invalid argument) 5591 [4016d3b1] gettimeofday({1045087224, 29417}, NULL) = 0 5591 [4016d3b1] gettimeofday({1045087224, 29535}, NULL) = 0 5591 [4016d3b1] gettimeofday({1045087224, 29594}, NULL) = 0

marek

/ Brevbäraren

Fel OS. :P

/ David Hedbor

Previous text:

2003-02-12 23:14: Subject: Re: Weird problem with Image.SVG in Pike 7.4/7.5

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truss.

/ Per Hedbor ()