Re: strtok, bus error
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thank you for that precise explanation. objdump is now less cryptic to me... - ben Glynn Clements a écrit :
ben wrote:i don't know if it is a compiler feature (storage behavior into the DATA segment), or a linux kernel feature, or if it is specified in ANSI, but the second way leads to pointing to a _constant_ string. If someone can enlighten...ANSI C says that string literals "may" be read-only. On platforms with memory protection they usually are read-only. On Linux, string literals are stored in the "rodata" segment, which is read-only, and thus can be shared between all processes which are using a given executable or shared library. You can list the segments which make up an executable or shared library using "objdump -h" [snipped] The main ones are text, rodata, data, and bss. The text segment holds code, and is read-only and executable (CODE flag). The others hold static data: global variables, "static" local variables, string literals, and intialisers for automatic (non-"static" local) arrays. Read-only data (literals, initialisers, "const" variables) goes into the rodata segment, which is read-only. Mutable variables with explicit initialisers go into the data segment. Mutable variables without initialisers (i.e. implicitly initialised to zero) go into the bss segment. As the entire bss segment is initially zero, it doesn't need to be stored in the file (this is indicated by the lack of the CONTENTS, LOAD, and CODE/DATA flags). The other segments tend to be architecture-specific.
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