1. 查找某个关键字（比如函数名）：
$ git grep xmmap config.c: contents = xmmap(NULL, contents_sz, PROT_READ,
diff.c: s->data = xmmap(NULL, s->size, PROT_READ, MAP_PRIVATE, fd, );
git-compat-util.h: extern void *xmmap(void *start, size_t length, int prot, int fla
read-cache.c: mmap = xmmap(NULL, mmap_size, PROT_READ | PROT_WRITE, MAP_PRIVATE,
refs.c: log_mapped = xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, logfd, );
sha1_file.c: map = xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, fd, );
sha1_file.c: idx_map = xmmap(NULL, idx_size, PROT_READ, MAP_PRIVATE, fd, );
sha1_file.c: win->base = xmmap(NULL, win->len,
sha1_file.c: map = xmmap(NULL, *size, PROT_READ, MAP_PRIVATE, f
sha1_file.c: buf = xmmap(NULL, size, PROT_READ, MAP_PRIVATE, fd, );
wrapper.c: void *xmmap(void *start, size_t length,
1.1 如果要显示行号，添加‘-n’选项：
$ git grep -n xmmap config.c:: contents = xmmap(NULL, contents_sz, PROT_READ,
diff.c:: s->data = xmmap(NULL, s->size, PROT_READ, MAP_PRIVATE, fd,
git-compat-util.h:: extern void *xmmap(void *start, size_t length, int prot, int
read-cache.c:: mmap = xmmap(NULL, mmap_size, PROT_READ | PROT_WRITE, MAP_
refs.c:: log_mapped = xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, logfd, );
sha1_file.c:: map = xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, fd, );
sha1_file.c:: idx_map = xmmap(NULL, idx_size, PROT_READ, MAP_PRIVATE, fd
sha1_file.c:: win->base = xmmap(NULL, win->len,
sha1_file.c:: map = xmmap(NULL, *size, PROT_READ, MAP_PR
sha1_file.c:: buf = xmmap(NULL, size, PROT_READ, MAP_PRIVATE, fd
wrapper.c:: void *xmmap(void *start, size_t length,
1.2 如果只显示文件名，添加‘--name-only’选项：
$ git grep --name-only xmmap config.c
diff.c
git-compat-util.h
read-cache.c
refs.c
sha1_file.c
wrapper.c
1.3 统计每个文件里有多少行匹配内容，添加‘-c’选项：
$ git grep -c xmmap config.c:
diff.c:
git-compat-util.h:
read-cache.c:
refs.c:
sha1_file.c:
wrapper.c:
1.4 查找git仓库里某个特定版本里的内容，添加tag名或sha号：
$ git grep xmmap v1.5.0 v1.5.0:config.c: contents = xmmap(NULL, st.st_size, PROT_READ,
v1.5.0:diff.c: s->data = xmmap(NULL, s->size, PROT_READ, MAP_PRIVATE, fd,
v1.5.0:git-compat-util.h:static inline void *xmmap(void *start, size_t length,
v1.5.0:read-cache.c: cache_mmap = xmmap(NULL, cache_mmap_size,
v1.5.0:refs.c: log_mapped = xmmap(NULL, st.st_size, PROT_READ, MAP_PRIVATE, logfd
v1.5.0:sha1_file.c: map = xmmap(NULL, st.st_size, PROT_READ, MAP_PRIVATE, fd,
v1.5.0:sha1_file.c: idx_map = xmmap(NULL, idx_size, PROT_READ, MAP_PRIVATE, fd
v1.5.0:sha1_file.c: win->base = xmmap(NULL, win->len,
v1.5.0:sha1_file.c: map = xmmap(NULL, st.st_size, PROT_READ, MAP_PRIVATE, fd,
v1.5.0:sha1_file.c: buf = xmmap(NULL, size, PROT_READ, MAP_PRIVATE, fd
1.5 查找git仓库里某个特定版本、特定文件里的内容（省略版本，默认当前版本），添加tag名或sha号、文件名：
$ git grep xmmap v1.5.0 diff.c v1.5.0:diff.c: s->data = xmmap(NULL, s->size, PROT_READ, MAP_PRIVATE, fd,
2. 某些关键字的逻辑组合
2.1 与逻辑：某一行既包括...又包括...
------------------->$ git grep -e 'pu' --and -e 'lic'
a.txt:public
c.txt:public
c.txt:public
2.2 或逻辑：某一行包括...或者包括...
------------------->$ git grep -e 'public' --or -e 'void'
a.txt:public
a.txt:void
b.txt:void
c.txt:public
c.txt:public
--or 是默认行为，如果省略：
------------------->$ git grep -e 'public' --or -e 'void'
a.txt:public
a.txt:void
b.txt:void
c.txt:public
c.txt:public ------------------->$ git grep -e 'public' -e 'void'
a.txt:public
a.txt:void
b.txt:void
c.txt:public
c.txt:public
2.3 非逻辑：某一行不包括...
------------------->$ git grep --not -e 'public'
a.txt:ab
a.txt:bc
a.txt:void
b.txt:void
b.txt:aaa
b.txt:bbb
c.txt:kkkk
c.txt:sfs
c.txt:l
2.4 组合逻辑：与或非的组合（为测试组合逻辑，又在库中新添加了d.txt文件）
------------------->$ git grep -e 'public' --and \( -e 'void' -e 'return' \)
d.txt:public void int save
d.txt:public void string save
d.txt:public return a ------------------->$ git grep -e 'public' --and \( -e 'void' --or -e 'return' \)
d.txt:public void int save
d.txt:public void string save
d.txt:public return a ------------------->$ git grep -e 'public' --and \( -e 'void' --and -e 'int' \)
d.txt:public void int save ------------------->$ git grep -e 'public' --and \( --not -e 'int' \)
a.txt:public
c.txt:public
c.txt:public
d.txt:public void string save
d.txt:public return a
2.5 全匹配：某一文件既包含...又包含...
------------------->$ git grep --all-match -e 'public' -e 'void'
a.txt:public
a.txt:void
d.txt:public void int save
d.txt:public void string save
d.txt:public return a
2.6 以上各个命令还可以加‘-n'、’-c‘、’--name-only‘、版本、文件等限制
2.7 查找某个字符串在何时添加
git log -S"string wanted to search" --oneline
81fbf7e a commit