- 论坛徽章:
- 0
|
一直想弄明白gensub(/xx/,"\\n",1,$1)中\n这个用法的意思
- [root@Mylinux tmp]# echo "abc||abc123 123abc xyz123" | awk '{print gensub(/abc/,"\\0",1,$1)}'
- abc||abc123
- [root@Mylinux tmp]# echo "abc||abc123 123abc xyz123" | awk '{print gensub(/abc/,"\\2",1,$1)}'
- ||abc123
- [root@Mylinux tmp]# echo "abc||abc123 123abc xyz123" | awk '{print gensub(/abc/,"\\3",1,$1)}'
- ||abc123
复制代码
试到\4,出现了惊奇一幕
- [root@Mylinux tmp]# echo "abc||abc123 123abc xyz123" | awk '{print gensub(/abc/,"\\4",1,$1)}'
- *** glibc detected *** awk: malloc(): memory corruption: 0x08099f10 ***
- ======= Backtrace: =========
- /lib/libc.so.6[0xb7e31e36]
- /lib/libc.so.6(__libc_malloc+0x90)[0xb7e337c0]
- /lib/libc.so.6[0xb7def93a]
- /lib/libc.so.6[0xb7dedd6f]
- /lib/libc.so.6[0xb7ded73e]
- /lib/libc.so.6(dcgettext+0x43)[0xb7dec7c3]
- awk[0x806e474]
- [0xb7f64420]
- awk(do_gensub+0x285)[0x8058a25]
- awk(r_tree_eval+0x397)[0x8081c47]
- awk(do_print+0x109)[0x805aec9]
- awk(interpret+0x453)[0x8080233]
- awk(interpret+0x1a0)[0x807ff80]
- awk(do_input+0x44)[0x806d3d4]
- awk(main+0x10ff)[0x806f5bf]
- /lib/libc.so.6(__libc_start_main+0xe0)[0xb7ddf0c0]
- awk[0x804c9a1]
- ======= Memory map: ========
- 08048000-08090000 r-xp 00000000 03:01 704528 /bin/gawk
- 08090000-08091000 rw-p 00048000 03:01 704528 /bin/gawk
- 08091000-080b7000 rw-p 08091000 00:00 0 [heap]
- b7900000-b7921000 rw-p b7900000 00:00 0
- b7921000-b7a00000 ---p b7921000 00:00 0
- b7a4b000-b7a55000 r-xp 00000000 03:01 786438 /lib/libgcc_s-4.2.1-20060612.so.1
- b7a55000-b7a56000 rw-p 00009000 03:01 786438 /lib/libgcc_s-4.2.1-20060612.so.1
- b7a6c000-b7a73000 r--s 00000000 03:01 1388963 /usr/lib/gconv/gconv-modules.cache
- b7a73000-b7b88000 r--p 03a4f000 03:01 1385071 /usr/lib/locale/locale-archive
- b7b88000-b7bc8000 r--p 01a14000 03:01 1385071 /usr/lib/locale/locale-archive
- b7bc8000-b7dc8000 r--p 00000000 03:01 1385071 /usr/lib/locale/locale-archive
- b7dc8000-b7dc9000 rw-p b7dc8000 00:00 0
- b7dc9000-b7f1a000 r-xp 00000000 03:01 786461 /lib/libc-2.6.so
- b7f1a000-b7f1c000 r--p 00151000 03:01 786461 /lib/libc-2.6.so
- b7f1c000-b7f1d000 rw-p 00153000 03:01 786461 /lib/libc-2.6.so
- b7f1d000-b7f20000 rw-p b7f1d000 00:00 0
- b7f20000-b7f46000 r-xp 00000000 03:01 786469 /lib/libm-2.6.so
- b7f46000-b7f47000 r--p 00025000 03:01 786469 /lib/libm-2.6.so
- b7f47000-b7f48000 rw-p 00026000 03:01 786469 /lib/libm-2.6.so
- b7f48000-b7f4b000 r-xp 00000000 03:01 786467 /lib/libdl-2.6.so
- b7f4b000-b7f4c000 r--p 00002000 03:01 786467 /lib/libdl-2.6.so
- b7f4c000-b7f4d000 rw-p 00003000 03:01 786467 /lib/libdl-2.6.so
- b7f4d000-b7f4e000 rw-p b7f4d000 00:00 0
- b7f64000-b7f65000 r-xp b7f64000 00:00 0 [vdso]
- b7f65000-b7f80000 r-xp 00000000 03:01 786454 /lib/ld-2.6.so
- b7f80000-b7f81000 r--p 0001a000 03:01 786454 /lib/ld-2.6.so
- b7f81000-b7f82000 rw-p 0001b000 03:01 786454 /lib/ld-2.6.so
- bfe04000-bfe19000 rw-p bffeb000 00:00 0 [stack]
- 已放弃
复制代码 |
|