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| author | Glenn L McGrath | 2000-09-11 00:32:13 +0000 |
|---|---|---|
| committer | Glenn L McGrath | 2000-09-11 00:32:13 +0000 |
| commit | f0b073f55ac00a87c38e4e7aa66ee3543564779b (patch) | |
| tree | 5a2024cd2cf880f4e4b861acab636e11bc14d5b7 | |
| parent | de34e4375565cbe1b60c2d99afddfb6c7c45b3ad (diff) | |
| download | busybox-f0b073f55ac00a87c38e4e7aa66ee3543564779b.zip busybox-f0b073f55ac00a87c38e4e7aa66ee3543564779b.tar.gz | |
dd now truncates files at the end its write, this can be turned of by
specifying conv=notrunc in the command line
This conforms to GNU dd behaviour
| -rw-r--r-- | coreutils/dd.c | 13 | ||||
| -rw-r--r-- | dd.c | 13 |
2 files changed, 20 insertions, 6 deletions
diff --git a/coreutils/dd.c b/coreutils/dd.c index 84f3211..5ab0a90 100644 --- a/coreutils/dd.c +++ b/coreutils/dd.c @@ -48,6 +48,7 @@ extern int dd_main(int argc, char **argv) int outFd; int inCc = 0; int outCc; + int trunc=TRUE; long blockSize = 512; uintmax_t skipBlocks = 0; uintmax_t seekBlocks = 0; @@ -57,6 +58,7 @@ extern int dd_main(int argc, char **argv) uintmax_t totalSize; uintmax_t readSize; unsigned char buf[BUFSIZ]; + char *keyword = NULL; argc--; argv++; @@ -69,7 +71,7 @@ extern int dd_main(int argc, char **argv) outFile = ((strchr(*argv, '=')) + 1); else if (strncmp("count", *argv, 5) == 0) { count = getNum((strchr(*argv, '=')) + 1); - if (count <= 0) { + if (count < 0) { errorMsg("Bad count value %s\n", *argv); goto usage; } @@ -92,7 +94,10 @@ extern int dd_main(int argc, char **argv) errorMsg("Bad seek value %s\n", *argv); goto usage; } - + } else if (strncmp(*argv, "conv", 4) == 0) { + keyword = (strchr(*argv, '=') + 1); + if (strcmp(keyword, "notrunc") == 0) + trunc=FALSE; } else { goto usage; } @@ -141,7 +146,9 @@ extern int dd_main(int argc, char **argv) break; outTotal += outCc; } - + if (trunc == TRUE) { + ftruncate(outFd, lseek(outFd, 0, SEEK_CUR)); + } /* Note that we are not freeing memory or closing * files here, to save a few bytes. */ #ifdef BB_FEATURE_CLEAN_UP @@ -48,6 +48,7 @@ extern int dd_main(int argc, char **argv) int outFd; int inCc = 0; int outCc; + int trunc=TRUE; long blockSize = 512; uintmax_t skipBlocks = 0; uintmax_t seekBlocks = 0; @@ -57,6 +58,7 @@ extern int dd_main(int argc, char **argv) uintmax_t totalSize; uintmax_t readSize; unsigned char buf[BUFSIZ]; + char *keyword = NULL; argc--; argv++; @@ -69,7 +71,7 @@ extern int dd_main(int argc, char **argv) outFile = ((strchr(*argv, '=')) + 1); else if (strncmp("count", *argv, 5) == 0) { count = getNum((strchr(*argv, '=')) + 1); - if (count <= 0) { + if (count < 0) { errorMsg("Bad count value %s\n", *argv); goto usage; } @@ -92,7 +94,10 @@ extern int dd_main(int argc, char **argv) errorMsg("Bad seek value %s\n", *argv); goto usage; } - + } else if (strncmp(*argv, "conv", 4) == 0) { + keyword = (strchr(*argv, '=') + 1); + if (strcmp(keyword, "notrunc") == 0) + trunc=FALSE; } else { goto usage; } @@ -141,7 +146,9 @@ extern int dd_main(int argc, char **argv) break; outTotal += outCc; } - + if (trunc == TRUE) { + ftruncate(outFd, lseek(outFd, 0, SEEK_CUR)); + } /* Note that we are not freeing memory or closing * files here, to save a few bytes. */ #ifdef BB_FEATURE_CLEAN_UP |