If you do not specify outfile, objcopy creates a temporary file and destructively renames the result with the name of infile. -I bfdname --input-target=bfdname Consider the source file's object format to be bfdname, rather than attempting to deduce it. -O bfdname --output-target=bfdname Write the output file using the object format bfdname.
Full Answer
How does objcopy work?
objcopy creates temporary files to do its translations and deletes them afterward. objcopy uses BFD to do all its translation work; it has access to all the formats described in BFD and thus is able to recognize most formats without being told explicitly. See section `BFD' in Using LD .
How does objcopy generate a raw binary file?
When objcopy generates a raw binary file, it will essentially produce a memory dump of the contents of the input object file. All symbols and relocation information will be discarded. The memory dump will start at the load address of the lowest section copied into the output file.
What is bfdname in Linux?
Use bfdname as the object format for both the input and the output file; i.e., simply transfer data from source to destination with no translation. Useful when transforming a raw binary input file into an object file. In this case the output architecture can be set to bfdarch.
What happens if you don't specify outfile in objcopy?
If you do not specify outfile, objcopy creates a temporary file and destructively renames the result with the name of infile . Consider the source file's object format to be bfdname, rather than attempting to deduce it. Write the output file using the object format bfdname .
What is objcopy in GNU?
The GNU objcopy utility copies the contents of an object file to another. objcopy uses the GNU BFD Library to read and write the object files. It can write the destination object file in a format different from that of the source object file. The exact behavior of objcopy is controlled by command-line options.
What is underscore in objcopy?
The most common such character is underscore, which compilers often add before every symbol. This option tells objcopy to change the leading character of every symbol when it converts between object file formats. If the object file formats use the same leading character, this option has no effect.
What is the copyright for GNU?
Copyright (c) 1991-2021 Free Software Foundation, Inc. Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.3 or any later version published by the Free Software Foundation; with no Invariant Sections, with no Front-Cover Texts, and with no Back-Cover Texts. A copy of the license is included in the section entitled "GNU Free Documentation License".
When generating an S-record or a raw binary file, it may be helpful to use -S
When generating an S-record or a raw binary file, it may be helpful to use -S to remove sections containing debugging information. In some cases -R will be useful to remove sections which contain information that is not needed by the binary file.
Can objcopy change endianness?
Note--- objcopy is not able to change the endianness of its input files. If the input format has an endianness (some formats do not), objcopy can only copy the inputs into file formats that have the same endianness or which have no endianness (e.g., srec ). (However, see the --reverse-bytes option.)
What is objcopy in GNU?
The GNU objcopy utility copies the contents of an object file to another. objcopy uses the GNU BFD Library to read and write the object files. It can write the destination object file in a format different from that of the source object file. The exact behavior of objcopy is controlled by command-line options.
How does objcopy work?
objcopy can be used to generate a raw binary file by using an output target of binary (e.g., use -O binary ). When objcopy generates a raw binary file, it will essentially produce a memory dump of the contents of the input object file. All symbols and relocation information will be discarded.
What is the GNU Free Documentation License?
Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.1 or any later version published by the Free Software Foundation; with no Invariant Sections, with no Front-Cover Texts, and with no Back-Cover Texts. A copy of the license is included in the section entitled GNU Free Documentation License.
What is underscore in objcopy?
The most common such character is underscore, which compilers often add before every symbol. This option tells objcopy to change the leading character of every symbol when it converts between object file formats. If the object file formats use the same leading character, this option has no effect.
Can objcopy copy a file?
The exact behavior of objcopy is controlled by command-line options. Note that objcopy should be able to copy a fully linked file between any two formats. However, copying a relocatable object file between any two formats may not work as expected.
Can objcopy change endianness?
Note--- objcopy is not able to change the endianness of its input files. If the input format has an endianness (some formats do not), objcopy can only copy the inputs into file formats that have the same endianness or which have no endianness (e.g., srec ).