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author | Mole Shang <[email protected]> | 2024-02-17 11:55:33 +0800 |
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committer | Mole Shang <[email protected]> | 2024-02-17 12:22:07 +0800 |
commit | e8e0a7b4c97064eb5e9415726d7e38aaceccd3fd (patch) | |
tree | fb42ba5be7a8ae608b968266f62fd71fa889a89d /user/pingpong.c | |
parent | a6af72924b115c1177d18d9b1eaba56623e4248b (diff) | |
parent | d85aec2689c4250d0384904bdc11aa618c726bec (diff) | |
download | xv6-labs-e8e0a7b4c97064eb5e9415726d7e38aaceccd3fd.tar.gz xv6-labs-e8e0a7b4c97064eb5e9415726d7e38aaceccd3fd.tar.bz2 xv6-labs-e8e0a7b4c97064eb5e9415726d7e38aaceccd3fd.zip |
Merge branch 'thread' into fs
Conflicts:
.gitignore
Makefile
conf/lab.mk
kernel/param.h
Diffstat (limited to 'user/pingpong.c')
-rw-r--r-- | user/pingpong.c | 44 |
1 files changed, 44 insertions, 0 deletions
diff --git a/user/pingpong.c b/user/pingpong.c new file mode 100644 index 0000000..7b03a76 --- /dev/null +++ b/user/pingpong.c @@ -0,0 +1,44 @@ +#include "kernel/types.h" +#include "user/user.h" + +int +main(int argc, char* argv[]) +{ + int p[2]; + + if (argc > 1) { + fprintf(2, "usage: pingpong\n"); + exit(1); + } + + pipe(p); + + int pid = fork(); + + if (pid == 0) { + short n; + read(p[0], &n, sizeof(n)); + if (n == 42) { + fprintf(1, "%d: received ping\n", getpid()); + } + n++; + write(p[1], &n, sizeof(n)); + close(p[0]); + close(p[1]); + exit(0); + } + + short n = 42; + + write(p[1], &n, sizeof(n)); + read(p[0], &n, sizeof(n)); + if (n == 43) { + fprintf(1, "%d: received pong\n", getpid()); + } + close(p[0]); + close(p[1]); + + wait(0); + + exit(0); +} |