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sd_json_variant_unset_field(3) — Linux manual page

SD_JSON...ET_FIELD(3)  sd_json_variant_unset_fieldSD_JSON...ET_FIELD(3)

NAME        top

       sd_json_variant_unset_field - Remove a specific field from a JSON       object

SYNOPSIS        top

#include <systemd/sd-json.h>int sd_json_variant_unset_field(sd_json_variant **object,const char *field);

DESCRIPTION        top

sd_json_variant_unset_field()takes a pointer to a pointer to a       JSON object and a field name. If the object contains a field under       the specified name, a new JSON object is allocated that is a copy       of the original one, however the specified field is removed. The       object parameter is updated to point to the new object, which has       an initial reference counter of one. The reference counter of the       original object is decremented by one. Or in other words: the       specified object is replaced by one with the field removed.       If the referenced object does not contain a field matching the       specified name, no operation is executed.       Similar, if aNULLpointer is referenced, no operation is       executed.

RETURN VALUE        top

       On success, and if a field was removedsd_json_variant_unset_field()returns a positive non-zero integer.       If no matching field was found it returns zero. On failure, it       returns a negative errno-style error code.Errors       Returned errors may indicate the following problems:-EINVAL           An argument is invalid.-ENOMEM           Memory allocation failed.

NOTES        top

       Functions described here are available as a shared library, which       can be compiled against and linked to with thelibsystemd pkg-config(1) file.       The code described here usesgetenv(3), which is declared to be       not multi-thread-safe. This means that the code calling the       functions described here must not callsetenv(3) from a parallel       thread. It is recommended to only do calls tosetenv()from an       early phase of the program when no other threads have been       started.

HISTORY        top

sd_json_variant_unset_field()was added in version 258.

SEE ALSO        top

systemd(1),sd-json(3)

COLOPHON        top

       This page is part of thesystemd (systemd system and service       manager) project.  Information about the project can be found at       ⟨http://www.freedesktop.org/wiki/Software/systemd⟩.  If you have a       bug report for this manual page, see       ⟨http://www.freedesktop.org/wiki/Software/systemd/#bugreports⟩.       This page was obtained from the project's upstream Git repository       ⟨https://github.com/systemd/systemd.git⟩ on 2025-02-02.  (At that       time, the date of the most recent commit that was found in the       repository was 2025-02-02.)  If you discover any rendering       problems in this HTML version of the page, or you believe there is       a better or more up-to-date source for the page, or you have       corrections or improvements to the information in this COLOPHON       (which isnot part of the original manual page), send a mail to       man-pages@man7.orgsystemd 258~develSD_JSON...ET_FIELD(3)

Pages that refer to this page:systemd.directives(7), systemd.index(7)

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