From 30106144fe6f065b36faf3833a930f78b828529a Mon Sep 17 00:00:00 2001 From: johannst Date: Sun, 13 Apr 2025 19:34:18 +0000 Subject: deploy: c929dc819132694c50a22eccb5c90b20aa39d97d --- print.html | 47 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 47 insertions(+) (limited to 'print.html') diff --git a/print.html b/print.html index 2d17d9e..7fa2797 100644 --- a/print.html +++ b/print.html @@ -1004,6 +1004,7 @@ status -f # abs path of current file
  • xargs
  • grep
  • find
    • +
  • dd

    • awk(1)

    awk [opt] program [input]
@@ -1477,6 +1478,43 @@ exec modifier characters ; and + also may need to be e
 > find . -maxdepth 1 -type d -exec echo x {} +
 # x . ./.github ./book ./src ./.git ./docs
    +

    dd(1)

    +

    Copy data block-wise.

    +
    dd [opts]
+    if=<path>         input file to read (stdin in case not specified)
+    of=<path>         oputput file to write
+    status=progress   show progress while copying
+    bs=<bytes>        block size
+    count=<n>         copy only <n> blocks
+    skip=<n>          skip <n> blocks in input (seek input)
+    seek=<n>          skip <n> blocks in oputput (seek output)
+    conv=<conv>
+         notrunc      dont truncate output file
+         excl         fail if output already exists
+         nocreat      fail if output does not exists
+
    +

    Example: bootstick

    +
    dd bs=4M if=<iso> of=<blkdev> oflag=sync status=progress
+
    +

    Example: patch file in place

    +
    # Create a 1024 bytes file filled with zeros.
+dd if=/dev/zero of=disk bs=512 count=2
+
+# Overwrite 4 bytes starting at byte 0.
+printf "aaaa" | dd of=disk bs=1 seek=0 conv=notrunc
+
+# Overwrite 4 bytes starting at byte 512.
+printf "bbbb" | dd of=disk bs=1 seek=512 conv=notrunc
+
+hexdump disk
+# 0000000 6161 6161 0000 0000 0000 0000 0000 0000
+# 0000010 0000 0000 0000 0000 0000 0000 0000 0000
+# *
+# 0000200 6262 6262 0000 0000 0000 0000 0000 0000
+# 0000210 0000 0000 0000 0000 0000 0000 0000 0000
+# *
+# 0000400
+

    Tools